Home Page arrow Chess Life Online arrow 2009 arrow The Games of Mark Diesen (1957-2008): Part I
The Games of Mark Diesen (1957-2008): Part I Print E-mail
By IM Mark Ginsburg   
January 12, 2009
Mark Diesen (September 16,1957 -December 9, 2008), World Junior Champ 1976, had a rare combination of positional insight and tactical accuracy.  He was well on his way to becoming Grandmaster when he fell off the rails in 1980 due to a common social problem in the USA, narcotics.  To put the problem in a global perspective, once German GM Eric Lobron told me he lost innumerable friends of his that he counted as more talented as him at chess to this scourge.  To Mark’s credit, he made a complete about-face, ridding himself of the situation that was the total destruction of so many and completing a college degree.  He subsequently began working as an engineer in the south (Louisiana and Texas) at various energy companies.   He also returned to chess off and on, but never to the serious degree of his ascendancy in the 70s.  

He grew up in Potomac Maryland, the next town over from Bethesda and Chevy Chase where I and future IM Steve Odendahl resided.  Also nearby were Eugene and John Meyer, Larry Kaufman, Richard Delaune, Robert Eberlein, Allan Savage, Charlie Powell, and many other strong masters.  It was quite a concentrated chess area and many hours were spent wiling way the time at blitz with Mark D., me, and Phil (“Flippy”) Goulding.  Later in life, both Goulding and Diesen would go on to win the Texas State Championship.   I also remember fondly social outings we made to visit Diana Lanni at her job in D.C. and trips over to Larry Kaufman’s chess club in Silver Spring, Maryland.

The apex of Mark’s career was the 1st place finish at the 1976 World Junior Championship.  Mark defeated Schussler, Sisniega, and others (drawing Vladimirov and Ftacnik) to take top honors.  His coach, GM Lubomir Kavalek, documented this tournament very well in a two-part article, March and April 1977, Chess Life and Review.

Mark's play reminded me of GM Huebner’s style – take what you are given, and display accuracy converting superior positions.  He also practiced controlled aggression – attack when the position demands it – this latter quality is reminiscent of GM Portisch.  All in all, he struck me as a very “European” player – worlds apart from the piece-sacking barbarians one often runs into at American Swisses.  I have found that studying this type of play is quite important to improve tournament results.  The “iron logic” of Smyslov, Botvinnik, Petrosian, and so on can be distilled into simply taking what one is given and then putting the opponent in an iron vice of technique.  In Diesen’s games, we see this time and again.

Here’s a game where he, at a young age (15), conducted a nice attack versus the 1967 World Junior Champ, Julio Kaplan.


1.e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 d6 6. Be2 Be7 7. O-O Nc6 8. Be3 a6 9. a4 Bd7 10. f4 Qc7 11. Nb3 b6 12. Bf3 O-O 13. Qe2 Rfc8 14. g4

This position is dangerous, e.g. 14... h6 15. h4 Nh7 16. g5 hxg5 17. hxg5 Nb4 18. Qh2 e5 19. Kg2.
14...Be8 15. g5 Nd7 16. Bg4!

Position after 16.Bg4

An excellent move from young Diesen.  I saw this insight – tactical and positional vision to attack efficiently -  from a young GM-to-be Alex Sherzer many years later, for example in Sherzer-H. Olafsson, 1991.
16…Nc5 17. Qg2
Possible is 17. f5 Bd7 18. f6 Bf8 19. Nd4.
17... Na5
A better bet is 17... Nxb3 18. cxb3 Na5 19. f5 Nxb3 20. Ra3! but White retains good chances.
18. Nxc5?!  
Better is 18.Nxa5! bxa5 19. f5! Rab8 20. Rab1 Rb4 21. Qh3 Bd7 22. f6 Bf8 23. fxg7 Bxg7 24. Rxf7! Kxf7 25. Qxh7 shows an example of the dangers.
18... dxc5 19. Qh3 Rd8

19... Nc4! 20. Bc1 Rd8 21. b3 Nd6 22. f5 c4 with counterplay
20. f5! exf5 21. Bxf5 g6 22. Bf4
White also had the immediate 22. Be6! Qe5 23. Bd5 Nc6 24. Bf4 Qd4+ 25. Rf2 Rac8 26. Rd1 Qg7 27. Qg3 Rd7 28. e5 Nb4 29. e6 Rxd5 30. Rxd5 Nxd5 31. Nxd5 fxe6 32. Be5  crushing.
22... Qb7 23. Bg4 Bc6

Last chance for 23... Rd4! 24. Nd5 Rxe4 25. Nf6+ Bxf6 26. gxf6 h5! 27. Bxh5 Qd5! – a nice defense. Now it’s downhill rapidly for Kaplan. Diesen is about to land some heavy tactical blows.
24. Rae1
24. Be6 Rf8 25. Bd5
24... Rd4
24... Nc4 25. Be6! fxe6 26. Qxe6+ Kh8 27. Be5+ Nxe5 28. Qxe5+ Kg8 29. Qe6+ Kh8 30. Rf7 winning. 24... c4 25. Be3 Rf8 26. Qh6 Bc5 27. Bxc5 bxc5 28. Re3 also winning. 24... b5 25. Nd5 Nc4 26. Be6 Rf8 27. b3 Na3 28. Be5 Bxg5 29. Rf6 crushing.
25. Be5 Bxg5

Position after 26...Bxg5

26. Rxf7!! 
May be obvious to some NOW, but it takes good maneuvering for Black to get into this situation.
26... Qxf7 27. Be6 Rd7

 The rest was just mop-up.
28. Rf1 Rf8 29. Nd5 Bxd5 30. exd5
White can always take on f7.  Black could have resigned.
30... Nc4 31. Rxf7 Rdxf7 32. Bc3 h5 33. Qd3 Kh7 34. Bxf7 Rxf7 35. Qxc4 Be3+ 36. Kg2 Rf2+ 37. Kg3 Rf5 38. Qe4 1-0

A very nice attacking effort.

Now let’s see Diesen giving a positional lesson from the black side of this opening to a strong future GM, John Fedorowicz.  By and large, Diesen had the edge over his peers in experience and insight in his teen years.  He and his main peer, Larry Christiansen, were really super-class juniors.


1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 Qc7 6. Be2 a6 7. Be3 Nf6 8. O-O d6 9. f4 Be7 10. Qe1 O-O 11. Qg3 Bd7 12. Nf3

Nowadays people play 12. Rad1 b5 13. Bd3 more.

Position after 12...Nb4

An excellent reaction.
 13. e5?!

Possible and less committal is 13. Nd4 e5 14. fxe5 dxe5 15. Bh6 Ne8 16. Nb3 Be6 17. Rac1 Rd8.
13... Nfd5 14. Bd4 Nxc3 15. Bxc3 Nd5

Curiously, Black also has the strong and unusual move 15... f6! Since the knight on b4 is not really hanging due to Qb6+.  There might follow 16. exf6 Bxf6 17. Bxf6 Rxf6 18.c3 Nd5 19. Ng5 Qb6+ 20. Kh1 Ne3 21. Rfe1 Bc6 and Black is doing great.
16. Bd4 Qxc2

Position after 16...Qxc2

It’s safe!
17. Bd1 Qg6 18. Bb3 Qxg3 19. hxg3

 Diesen wrapped up convincingly.
19…Bb5 20. Rfc1 dxe5 21. Nxe5 Rfd8 22. a4 Be8 23. Bf2 Rdc8 24. Nd3 Nb4 25. Nxb4 Bxb4 26. Bd1 Bd2 27. Rxc8 Rxc8 28. Bf3 b5 29. a5 Bc6 30. Rd1 Bxa5 31. Ra1 Bd2 32. Rxa6 Bxf3 33. gxf3 h5 34. Kf1 Rc2 35. Bd4 Rc4

Position after 35...Rc4

The immediate 35... h4 36. gxh4 Rc4 also wins
36. Rd6 h4 37. Be5 Rc1+ 38. Kg2 Rc2 39. Kh3 hxg3 40. Kxg3 Be1+  41. Kh3 Kh7 42. Rb6 b4 0-1

Continuing in this theme of Diesen showing competitive superiority to fellow juniors his age or younger, here are wins over strong young talents Wilder, Rohde, DeFirmian, and McCambridge. 


Future GM and US Champion Michael Wilder was very tactically sharp and even at Wilder’s age of 16 (when this game was played) Diesen needed to be careful.  What we got was an inaccurate game but a good fight.
1.d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. Be2 O-O 6. Nf3 Bg4 7. Be3 e5 8. d5 Nh5 9. h3 Bd7 10. c5 Qe7 11. Qb3 Bc8 12. cxd6 cxd6 13. Nd2 Nf4 14. Bf1 f5 15. Nc4 Na6 16. O-O-O fxe4 17. Nxe4 Rd8 18. g3 Nh5 19. Qa3! b5 20. Na5! Bf5 21. Nc6 Qc7 22. Ng5!

Position after 22.Ng5

Diesen played the last five moves according to the computer's 'first line' and has a crushing advantage. 
22...Nb8 23. Bxb5 Nxc6 24. Bxc6?
Showing that he is human.  The right move was 24. dxc6! Nf6 25. g4 Bc8 26. f4 e4 27. Bd4! and white will win easily.
24... h6?
Strong is 24... Nf6! and White has to do contortions like 25. Kd2 and the game is up in the air.
25. g4 Bd7 26. gxh5 hxg5 27. Bxg5 Rdc8 28. hxg6?!

Easiest was 28. Kb1! Bxc6 29. dxc6 Qxc6 30. Qb3+ Qc4 31. Qxc4+ Rxc4 32. hxg6 and wins.
28... Bxc6 29. dxc6 Qxc6+ 30. Kb1  

Position after 30.Kb1

The last blunder. Necessary was 30... Qc2+ 31. Ka1 Rab8 32. Rc1 Qxg6 33. Be3.
31. Qd3 Kh8 32. Bc1 Rab8 33. Qf5 
Black now collapses.
33… e4 34. Qh5+ Kg8 35. Qxd5+ Qxd5 36. Rxd5 Rf8 37. Rh2 Rb6 38.Rg2 Rc8 39. h4 Rbc6 40. Rd1 Rc2 41. Rd8+ 1-0

Here’s an important win for Diesen in the 1976 US Junior over another future Grandmaster, featuring a nice attack and steady progress in the ending.


1. e4 d6 2. d4 g6 3. Nf3 Nf6 4. Nc3 Bg7 5. Be2 O-O 6. O-O c6 7. h3 b5 8. e5 Ne8 9. Bf4 Bb7 10. Qd2 Nd7 11. Rfd1 Nb6 12. Bh6 Qc7 13. Bxg7 Nxg7 14. Bd3 f6 15.Qh6 Qd7 16. Re1 Rf7 17. Nh4 Ne6 18. Re3 dxe5 19. dxe5 f5 20. Rd1 Nd5 21. Rg3 Raf8 

Position after 21...Raf8
22. Bxf5!
A methodical buildup gives the successful preconditions for a sacrifice.  In this case, it’s not even a sacrifice.
22…Rxf5 23. Nxg6 Kf7 24. Qxh7+ Ke8 25. Nxd5 cxd5 26. Nxf8 Nxf8 27.Qh6 Rxe5 28. Rf3 Rf5 29. Rdd3 d4 30. Rxd4 Qxd4 31. Rxf5 Nd7 32. Rxb5 Be4

Position after 32...Be4

Black did well to escape the worst and now white settles down to the next phase of the game.  Slowly Diesen grinds his opponent down.
33. c3 Qd3 34. Rb4 Nf6 35. Qc1 Bc6 36. Qf1 Qd5 37. f3 Qxa2 38. Qc4 Qb1+ 39. Kh2 Bd5 40. Qd4 Qe1 41. Rb5 Qe6 42. Ra5 a6 43. Rc5 Kf7 44. c4 Bb7 45. Qe5 Qb6 46. Rc7 Qb4 47. Qc5 Qxc5 48. Rxc5 Ke6 49. Rc7 1-0
Points like this are as important as any other kind of win in a tournament.

Here’s another scrappy game from the same event.  Diesen does nothing special in the opening and even has the worst of it.  DeFirmian gets careless, though, and Diesen wakes up with some nice tactics.


1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. g3 g6 7. Bg2 Bg7 8. O-O O-O 9. h3 Nc6 10. Nde2 Bd7 11. Nd5 Nxd5 12. exd5 Ne5 13. Kh2 Rc8 14. Rb1 Qa5 15. a3 Qc5 16. c3

Position after 16.c3

A nice line for Black is 16... Bf5! 17. Be3 Qc4 18. b3 Qc7 19. Ra1 h5 20. c4 h4 21. g4 Bxg4! 22. hxg4 Nxg4+ 23. Kh3 Nxe3 24. fxe3 Bxa1 25. Qxa1 a5 with a great game.
17. Be3 Qc7

Playable is 17... Qc4 18. Nd4 h5.
18. Bd4 Bd3

Very simple and fine for Black is 18... Bxe2 19. Qxe2 Nc4.
 19. Ra1 Rfe8 20. Re1 Bf5 21. g4 Bd7
21... Bd3
22. Ng3 Qc4 23. b3 Qd3

Black has taken things too far.  Now White “wakes up”.
24. f4! Rxc3
24... Qxd1 25. Raxd1 Nxg4+ 26. hxg4 Bxg4 27. Rc1 Bxd4 28. cxd4 Rxc1 29. Rxc1 Rc8 30. Rc4! Bd7 31. Bh3 f5 32. Rxc8+ Bxc8 33. Ne4 Kg7 34. Kg3 h6 35. a4 Bd7 36. a5 and White will win.
25. Bxc3 Qxc3 26. Rc1 Qb2 27. fxe5 Bxe5 28. Qf3
The most direct is 28. Rc7 Rd8 29. Qc1 Qxb3 30. Rxe5 dxe5 31. Rxd7! 
28... f5
Black had to try 28... Qxa3 29. Rc7 Qa5 30. Rec1 Qb5 31. Bf1 Qa5 32. Qe3 Bc6 33. R7xc6 bxc6 34. dxc6 Rc8
29. gxf5

Position after 29.gxf5

29...Rf8 30. Kh1 Bxf5 31. Rf1 Qd4 32. Nxf5 1-0

In this next game from Lone Pine 1977, Diesen swamps young McCambridge’s King’s Indian, gaining space all over the board. One he seizes control of the b-file, Diesen infiltrates, leaving his opponent totally helpless.


1. c4 Nf6 2. Nc3 g6 3. e4 d6 4. d4 Bg7 5. Be2 O-O 6. Bg5 h6 7. Be3 e5 8. d5 Na6 9. Qd2 Kh7 10. f3 Bd7 11. O-O-O Nc5 12. g4 Ne8?!

12... a5,12... Na4 13. h4 Nxc3 14. Qxc3 a5 15. Nh3 Qe7 16. Kb1 a4 
13. h4 a6 14. Kb1 Qb8 15. b4! 

Position after 15.b4

Of course!  Take the space.
15… b5
15...Na4 16. Nxa4 Bxa4 17. Rc1 b5 18. c5  dxc5 19. Bxc5 Nd6 20. h5 g5 21. Nh3  this is also great for White. 
16. bxc5 b4 17. Ka1 bxc3 18. Qxc3 dxc5 19. Bxc5 Nd6
This position is terrible for Black.  Diesen continues accurately.
20. Bd3
Equally good is 20. h5 g5 21. Rb1 Qe8 22. Qa5.
20... Qc8 21. Ne2 Rb8 22. Rdg1 Rd8 23. h5 g5 24. Rb1 Bf8 25. Be3 f6
26. Rxb8 Qxb8 27. Rb1 Qc8 28. Qb3
Also strong is 28. c5 Nb5 29. Qa5 as happens soon in the game.
28... Kh8 29. c5 Nb5 30. a4 Na7 31. Qb7 

Position after 31.Qb7

Black could resign.
31…Qxb7 32. Rxb7 Nc6 33. dxc6 Bxc6 34. Rb3

 Bxa6 Bxb7 35. Bxb7 Rd3 36. Bc1 Bxc5)
34... Bxa4 35. Ra3 Bd1 36. Ng1 1-0 
A very convincing effort.

Now let’s see some Diesen wins versus established Grandmasters.


This exciting game had crazy roller coaster evaluation changes at the end of the first time control.

1. Nf3 Nf6 2. c4 g6 3. g3 Bg7 4. Bg2 O-O 5. O-O d6 6. d4 Nbd7 7. Nc3 e5 8. e4
exd4 9. Nxd4 Re8 10. Re1 Nc5 11. h3 a5 12. Qc2 c6 13. Be3 a4 14. Rad1 Nfd7 15. Re2 Qa5 16. Red2 Ne5 17. Bf1 a3!

Position after 17...a3

17... Qb4!? 18. a3 Qa5 is also fine.
18. b3 Nf3+! 19. Nxf3 Bxc3
This is equal.
20. Rxd6?!
The safest is 20. Bxc5 dxc5 21. Rd6 Bg7 22. Qd3 Qc3 23. Rd8 Be6 24. Rxa8 Rxa8 25. Qxc3 Bxc3 26. Ng5 and it’s dead equal.
20... Nxe4 21. R6d3 Bg7
21... Bb4! is good.
22. Bd4 Nc5 23. Bxg7 Kxg7 24. Rd4 Bf5 25. Qc1 Ne4?!

Browne starts to get careless.  25... Re7! 26. g4 Be6! 
26. g4 c5 
Giving up key squares.  But, 26... Bc8 27. Qf4 was scary.
27. R4d3 Be6 28. Qf4! Nf6 29. Ng5 Ra6 30. Rf3
Here white had 30. Bg2! with a sample line 30…Bc8
31. Bd5 h6 32. Nxf7 Nxd5 33. Rxd5 Rf6 34. Qxh6+ Kxf7 35. Qh7+ Kf8 36. Qh8+ Kf7 37. Rd7+ {wins}.
30... Bc8 31. Rd6 Rxd6 32. Qxd6 Qd8 33. Qxc5 Re1 34. Re3 Ra1

Position after 34....Ra1

35. Qe7??
Diesen must have been in time trouble to miss the following lines. 35. Re7!  is crushing.  The funny point is 35…Qd3 36. Rxf7+ Kh6 37. Kg2!! (37. Kh2 also wins)
37…Qxf1+ (37... Rxf1 38. Nf3 wins) 38. Kg3 Qg1+ 39. Kh4! And this great king walk wins!
35... Qxe7 36. Rxe7 Rxa2 37. Rxf7+ Kh6 38. Nf3
Position after 38.Nf3

 Browne must also have been in acute time trouble.  He throws the game away at the moment where he had 38... Ne4!! 39. Bd3 Ng5 40. Nxg5 Kxg5 41. Kg2 Rd2 42. Bb1 Rb2 43. Kg3 Rxb3+ 44. f3 Kh6 45. h4 (45. Bc2 Be6 46. Re7 a2 47. h4 Bg8 and black wins) 45... Bxg4! And black wins.
39. g5+ 
Now White wins.  What a game! 
39… Kh5 40. gxf6 Rxf1+
Time trouble? Black can only play on with 40... Kh6 41. h4 a2 42. Ng5 Rxf1+ 43. Kxf1 a1=Q+ 44. Kg2 Kh5 45. Rxh7+ Kg4 46. f7 Qf6 47. f3+ Kf4 48. f8=Q Qxf8 49. Rf7+ Qxf7 50. Nxf7 Bf5 51. Kf2 Bc2 52. b4 Bd1 53. Ng5 Bb3 54. c5 Bc4 55. Nh3+ Ke5 and White wins, but of course Black must make him find this.
41. Kxf1 Bxh3+ 42. Ke2 a2 43. Rxh7+ Kg4 44. Rh4+ Kf5 45. Nd4+
Also winning is 45. f7 a1=Q 46. f8=Q+ Ke6 47. Nd4+
45... Kxf6 46. Nc2 1-0  
A very exciting game.

In the next game, Diesen exploits a tactical chance when GM Eugenio Torre plays too lackadaisically in a sharp Sicilian. Diesen goes on to win a smooth ending.


1.e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 d6 6. Bg5 Bd7 7. Qd2 a6 8.  O-O-O b5 9. Bxf6 gxf6 10. f4 e6 11. Kb1 Qb6

Also playable is 11... b4 12. Nce2 Qb6
12. Nf3 O-O-O
12... b4 13. Na4 Qa5 14. b3 Rd8 15. Nb2! with an edge.
13. f5 Kb8 14. fxe6 fxe6 15. g3 Qc5
15... Ne5! is Black’s best bet.
16. Bh3 Bc8
16... Ne5! 17. Nd4 Nc4 18. Qd3 Re8
17. Qe1 Bg7 18.Rf1 Rhe8 19. Ne2 Ne5

19... f5!? 20. exf5 exf5 21. Qd2 Be6
 20. Nfd4 Nc4 21. Rf3 d5 22. exd5 Rxd5 23. Rfd3 Ne5

Playable is 23... f5 24. Bg2 Rd6 25. Nb3 Qe5 26. Nbd4 Qc5
24. Rc3 Qb6? 

Position after 24...Qb6

A losing blunder.24... Nc4! 25. Bg2 Rd6 26. b3 e5 27. Nc6+ Rxc6 28. Bxc6 Qxc6 29.bxc4 bxc4 30. Ka1 Ka8 with compensation.
25. Rxc8+ Kxc8 26. Nxe6!
 Blammo!  Diesen dispatches the experienced GM.
26…Rxd1+ 27. Qxd1 Kb8
27...Rxe6 28. Nf4
28. Nxg7 Rd8

Watch Diesen’s technique as he wraps up effortlessly, snuffing out all conceivable counterplay every step of the way.
29. Qf1 Qe3 30. Nf5 Qf3

Position after 30..Qf3

31. Ned4 Qxf1+ 32. Bxf1 Kb7 33. c3 Kb6 34. Kc2 Ng4 35. h3 Ne5 36. Be2 Re8 37. Kd2 Ng6 38. Ne3 Rd8 39. Bd3 Rd7 40. Bf5 Rd8 41. a3 Ne7 42. Be4 h5 43. Bf3 Rg8 44. Nef5 Nxf5 45. Nxf5 Rg5 46. Be4 Rg8 47. h4 a5 48. Bf3 Rd8+ 49. Nd4 Rh8 50. Ne2 Kc5 51. b4+ Kb6 52. Nf4 Rg8 53. Nxh5 f5 54. Kd3 a4 55. Kd4 f4 56. g4 Rd8+ 57. Ke4 1-0

A very fine effort.

In my next and final installment, I will go over more Diesen efforts, including critical games from his triumph at the 1976 World Junior. 

Addendum:  a nice note from Dr. Eric Moskow:
Source: susanpolgar.blogspot.com
Mark, old friend I just heard the crushing news of your loss, I will never forget our game when we were both 5 -0 a dragon in us high school championship, we blitz the moves and  you with your genius beat me with your flag hanging, we were the pogo dancers in Sweden in 1976, we talked endlessly over the years on ICC, you were a life long friend even at a distance, The first bright light of the class of 76, even though you were a year ahead of us. I knew you loved your wife and kids who I never met, As a doctor I know life is fragile, your loss rocks my world, its unfortunate that I never really told you what a great memory I hold of our association. Your family will always cherish you and we will play again someday when I can even the score, rest in peace buddy. Eric D Moskow, M.D.

Author’s note: I remember the game referenced by Dr. Moskow very well.  At the time, I remember thinking Diesen’s positional experience would carry the day versus someone more booked up.  However, things don’t always turn out so cleanly and it was indeed a crazy time scramble.

Addendum 2:  Mark Diesen’s Chess Achievements

From Mark Diesen’s own ICC finger notes,

·    1973-74 1st Hastings Challengers
·    1976 World Junior Champion
·    several GM norms Karlovac 77' Polaniza Zdroj '78 etc
·    Texas State Champ 2001 & 2003

Mark Ginsburg received an IM Title in 1982.  He won the Manhattan CC Championship twice in 1988 and 1990. Also, co-winner, "Universe Open", San Francisco, 2000.  First place, Brugges Belgium 1990 ahead of Finegold and others  First place, Eeklo Belgium 1985 ahead of Hellers, Winants, and others. National Chess Congress, first place, 1978. Peak rating = 2578 (23rd in USA) in 1993.  Then entered the workforce, what a bad idea. Ginsburg maintains a blog at