Chelsea boss Andre Villas-Boas admits they were "not good enough" in their 1-1 draw at FA Cup opponents Birmingham City.

The Blues boss was reportedly challenged openly by some of his squad during frank exchanges, but if he was expecting a positive response, he failed to get it as they stuttered to a 1-1 draw against below-strength npower Championship opponents.

"We were not good enough," Villas-Boas said.

"Better in the second half but not enough to win the game.

"Never satisfying when you draw at home to a Championship team."

The latest in a long line of defensive mistakes this season saw Birmingham take the lead through David Murphy.

Daniel Sturridge eventually equalised but Chelsea simply did not do enough to merit a winner.

Villas-Boas, who hauled his players in on their day off on Sunday after a display at Everton he branded the "worst of the season", denied they had been as poor today.

"The team commitment was there and the team response was there straight after we suffered the setback," he said, pointing out they immediately won a penalty missed by Juan Mata.

"If the penalty goes in, it's 1-1 a little bit earlier and it gives you time to find the winner.

"It took us too much time to score the leveller."