North American Open Las Vegas 2012 Rd8

Here is another Cheng,Bindi game, this time from round 8 with Cheng on the white side. White had chances to take the upper hand in the topical g3 line. 

Cheng also has a Youtube Channel for chess Youtube barkyducky 

IM Cheng,Bindi(CAN)

Cheng,Bindi (2397)-Molner,M (2479)
Benoni g3 [A64]
22nd North American Open Las Vegas USA (8.11), 29.12.2012

Position 1
The position is tense. The mobile pawn center is white's major weapon. What should white do next?

White to Play

21...Nh5

Position 2
The battle lines are clearly marked. Black wants to destroy the pawn center and white's king. White wants to push forward. How should black proceed?


Black to Play

24.Qxb3