CHESS: Holding On

This is the position that I reached after White's 41st move against Fritz set to Master Level. Here are the moves:

I'd managed to maintain material equality but I'd been in defensive mode for most of the game, and I still was. I was certainly on the back foot. My three pieces were on the back rank and there were various threats looming. I decided to take a break from the game and analyse the situation before proceeding. Fritz's analysis showed that the best way forward for Black was to play 41...exf4, although White still maintains the advantage. The suggested continuation was:

This sequence of moves leads to the following position (constructed using ChessX):

The frustration for Black is that he can't play (in the first position) Nc6 to drive away the White Rook because the b pawn is then lost. In the continuation described, Black does play Nc6 but at a later date. In any case, the key move for Black to regain some sort of offensive does seem to lie with 41...exf4.