18.h3?
White's carelessness which is exploited very well by Matlakov.
18...B×h3! 19.g×h3 Q×h3
Black has now the idea of transferring the bishop to e3 via h6.
20.Qg5 d3 21.Qg2 Q×g2 22.K×g2 d×e2 23.Rf2 Rf4 24.R×e2 R×c4 -+

🔸Russian Team League 2018
🔸Round 1
⚪️Najer,Evgeniy (2667)
⚫️Shirov,Alexei (2652)
🔸0-1

18.c5!
An excellent positional pawn sacrifice to clear the c4 square for his knight.
18...d×c5 19.Nbd2 Nbd7 20.Nc4 Ne8 21.Ba4 Nd6 22.B×d7 Q×d7 23.Nc×e5 +-

🔸Russian Team League 2018
🔸Round 2
⚪️Fedoseev,Vladimir3 (2706)
⚫️Najer,Evgeniy (2667)
🔸1-0

39...f3??
The only way to continue fighting is 39...Kf7.
40.R×c8+ B×c8 41.Qe8+ 1-0

🔸Russian Team League 2018
🔸Round 2
⚪️Potkin,Vladimir (2574)
⚫️Gelfand,Boris (2695)
🔸1-0

26...B×d5? (26...N×d5)
A blunder. Gelfand has overlooked his opponent's next move.
27.Ba6! B×a2?
A)27...Rcd8 28.N×g6 +/-
B)Bb7 28.Rd7 +-
28.B×c8 R×c8 29.Rd7 Qc3 30.Re3 Qa1+ 31.Kh2 +-

⚪️#421 (Strategy-White to Move)
🔸Timman,J
🔸Portisch,L
🔸Antwerp 1989

📕White would have a clear advantage if he could drive the knight away from e5 with f2-f4. White's forces are almost all in place for this, so White played...
26.Rf1! Qg5?! This proves to be less good. 27.Ne2! Nf4 28.Nxf4 Qxf4 29.g3 Qf3 30.Ng4! Qxd1 31.Nf6+ Kh8 32.Rfxd1+/-

⚪️#422 (Strategy-White to Move)
🔸Portisch,L
🔸Timman,J
🔸Antwerp 1989

📕22.d6!
The knight will find a good square on c4 and the bishop on c6, while it is not immediately apparent how Black will be able to mobilize his own forces.
22...Qxa2 23.Qc4! Qb2 24.Bf3 Rab8 25.Bc6 Patience, my friend. 25...Red8 26.Qxc5 d3?! 27.Nb4!+/-

⚪️#423 (Strategy-White to Move)
🔸Karpov,A
🔸Van der Wiel,J
🔸Tilburg, 1988

Unity Chess Multiple Choice 423

B: Nd2 – 7
👍👍👍👍👍👍👍 88%

A: Bd3 – 1
👍 13%

C: Kf1
▫️ 0%

👥 8 people voted so far.

⚪️#424 (Strategy-White to Move)
🔸Karpov,A
🔸Hjartarson,J
🔸Seattle 1989

Unity Chess Multiple Choice 424

B: N×d4 – 5
👍👍👍👍👍👍👍 63%

C: Rc4 – 3
👍👍👍👍 38%

A: Rfc1
▫️ 0%

👥 8 people voted so far.

The Icelandic national team for the 1939 Buenos Aires Chess Olympiad. Left to right: J. Gudmundsson, E. Thorvaldsson, B. Möller, A. Asgeirsson, G. Arnlaugsson
(Source: Alt om Skak, 1943)

@UnityChess

Olafsson-Taimanov from Hastings 1955/56. This was Olafsson's international breakthrough, he shared 1st place with Korchnoi ahead of Ivkov and Taimanov.

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At the 1977 Dutch championship in Leeuwarden. Round 3, April 20. Jan Timman is in play v. Paul Boersma. Viktor Korchnoi, looks on; he won this event with 12/13.

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