Noteboom Variation, Anti-Noteboom Gambit

The Anti-Noteboom Gambit, 5. g3, avoids the Noteboom main lines, in which White tries to recover the c4-pawn with 5. a4 or 5. e3. White instead lets the pawn go and prepares Bg2, aiming the bishop down the long diagonal toward Black's queenside. Black most often holds the material with 5...b5, and 5...Nf6 is the main alternative. The line is rarely played. The engine rates it as balanced, and White scores well in online games.