LONDON: Luiz Felipe Scolari has responded defiantly to Chelsea's latest disappointment but knows his side cannot afford another setback when they begin their Christmas program against West Bromwich Albion.

Twice in the last two weeks Chelsea have failed to take the chance to claim top spot in the Premier League after leaders Liverpool slipped-up.

And on the most recent occasion - against Everton at Goodison Park - Chelsea suffered the additional blow of having skipper John Terry sent-off, triggering a three-match ban for the England defender.