N'Golo Kante is expected to miss some important encounters after being ruled out for three weeks with a muscle injury.
"N'Golo is not fit, he has a muscle injury similar to the one he came off recently against Arsenal with," Lampard said, according to Sky Sports. "Hopefully, it'll be three weeks."
The injury will result in Kante missing Chelsea's Champions League round of 16 matchup against Bayern Munich next week as well as an FA Cup fifth-round tie against Liverpool. He could, however, recover in time for the second leg against Bayern on March 18.
He'll also be sidelined for Premier League matches against Bournemouth, Everton, and, potentially, Aston Villa.
An ankle injury forced Abraham to miss Chelsea's 2-0 loss to Manchester United, while Christensen broke his nose in that match. Loftus-Cheek has yet to feature this season since rupturing his Achilles tendon in May.