Brazil forward Willian will face a late fitness test on his own Achilles issue, while Lampard revealed Ruben Loftus-Cheek and Christian Pulisic played in an "in-house game" at Chelsea's training ground on Friday.

Jorginho starts a two-match league suspension, while N'Golo Kante is still out with an adductor problem, Andreas Christensen remains doubtful and Tammy Abraham is out with his ankle complaint.

"Callum had a re-injury, yesterday," said Lampard, of Hudson-Odoi.

"We're having a scan on him this afternoon. So he will be longer than expected.

"It's tough, he wasn't rushed back, and we had all the signs that he was fit to train.

"Then he re-injured it on his first training session with us.

"So it's frustrating for him definitely, a young boy who's keen to play as you'd expect. And it's frustrating because it's another injury to us.

"It hasn't been spoken about that much, but we've had probably the worst injury list of certainly the top group of the table I think, lots of numbers injured, important players injured, Kante, Loftus-Cheek et cetera.

"We started the season that way and it's happened again in the middle of the season. And we're working against that to try to get the best results."

Long-term absentees Loftus-Cheek and Pulisic are inching towards a return to first-team action, but Lampard is loath to take any risks given Chelsea's injury record.

"We've just had an in-house game here, that Ruben and Christian Pulisic took part in," said Lampard.

"It was great to see Christian get some minutes, he's still short of match fitness, but it's the first time the injury's gone up to a level to get him on a big pitch in a relatively competitive match, so it's a big step forward hopefully.

"I'll found out how it went later, but I just watched it. And Ruben played half of that game himself, and is trying to find match fitness. He's short of that, and Ruben's saying that himself and I can see that.

"So there's work to be done with Ruben.

"Kovacic isn't fit, his Achilles injury will take him out of the weekend, but hopefully it will not be long after that.

"And Willian we are assessing, he's a question-mark for Sunday."