Positional pawn sacrifice
Hi! I found an interesting game where Boris Gelfand won by interesting positional d-pawn sacrifice. The game took place in Spain, 2006. Gelfand played against Sergei Tiviakov.
They chase the Hubner Variation in Nimzo-Indian Defence. The key problem in middle game after this opening is often white d-pawn. In this game the key problem was black's extra d-pawn.