The Week in Chess

Fabiano Caruana beat Vladimir Kramnik in an amazing game where fortunes fluctuated wildly. Kramnik's choice of variation against the Petroff seemed insipid and a draw likely. Caruana used a lot of time and this encouraged Kramnik to become ambitious, however the complications looked likely to lead to his defeat. Caruana's time trouble rescued him and Kramnik was better at move 40 and winning shortly afterwards, eg with 43.c4. Only a couple of moves later the position was back level following 45.c5+?. The position remained complicated but balanced for a long time before Kramnik went completely wrong with 58.Kb1?! and 59.Rd1?? allowing Caruana to claim a vital win and take the tournament lead.

Alexander Grischuk sacrificed a piece in a very sharp Semi-Slav against Ding Liren and got a large time advantage to boot. After 21.f4 Ding spent just 2 minutes over 21... gxf4 (21...h5 was best) which would have given Grischuk a decisive advantage had he played 22.Bh4 followed by Qg4. Rxf4 was played instead and the game eventually finished in a draw.

Levon Aronian managed to get an edge with black against Sergey Karjakin in the sharp Vienna Variation. 13..Qb4! seemed to surprise Karjakin. Karjakin tried to bail out into a difficult ending but it was too far gone to defend.

Shakhriyar Mamedyarov tried the Qc2 Nimzo-Indian against Wesley So but found his opponent very well prepared and very quickly the game reached sterile equality and a draw was agreed on move 31.

Round 4 standings: 1at Caruana 3pts, 2nd Kramnik 2.5pts, 3rd Mamedyarov 2.5pts, 4th Aronian 2pts, 5th Grischuk Alexander 2pts, 6tn Ding Liren 2pts, 7th= Karjakin, Wesley So 1pt

Round 5 Thursday 15th March 2pm GMT Aronian-Grischuk, Caruana-Karjakin, Wesley So-Kramnik, Ding Liren-Mamedyarov.