Jake Bidwell will be forced to sit out Brentford's FA Cup fourth-round clash with west London neighbours, and cup holders, Chelsea through suspension.
The youngster, on-loan from Everton, was sent off during the Bees' third tier clash with Leyton Orient on Tuesday.
Uwe Rosler is yet to decide who will provide cover at left-back, but Scott Barron is expected to step into the starting XI.
Midfielder Kevin O'Connor is still out with an ankle injury, but highly-rated Harry Forrester - who has been linked with a move to the Premier League - will come back in after being rested against Orient.
Eden Hazard will be missing for Chelsea as he starts a three-match ban.
The Belgian playmaker was dismissed in controversial circumstances at Swansea on Wednesday, with a red card brandished in his direction after kicking a ballboy.
Club captain John Terry, who has been eased back into competitive action following a lengthy spell out injured, could start as David Luiz is nursing a knock.
Rafa Benitez has few other concerns to contend with, with Yossi Benayoun and Oriol Romeu (both knee) the only players currently sidelined.
