Viswanathan Anand holds the edge going into the fifth game as white in his World Championship match against Boris Gelfand at the State Tretyakov Gallery here.
The fourth game was another piece of good preparation by Anand and another indication that Gelfand and his team are yet to even come close to cracking the opening repertoire of the Indian.
The Slav defense had been going through rough weathers lately but it's sure to get a revival post Anand's two successful games as black.
Playing for his fifth world title and third match in a row, Anand will now have to use his white pieces to maximum effect.
Gelfand may not have done well in his white games but it is clear that his surprise has worked well as black in the Grunfeld defense.
Anand, known to play the Grunfeld himself is still looking at ways to dent the system.
"The match is still developing and we are probing," quipped the world champion after game four of the USD 2.55 million championship. Gelfand knows that he has not been able to push Anand at all and the Indian ace is proving a very hard opponent.