London - N'Golo Kante will be sidelined for three weeks after suffering a muscle injury against Manchester United, Chelsea coach Frank Lampard said on Friday.
Kante limped off after 12 minutes of Monday's 2-0 defeat to United at Stamford Bridge and Blues boss Lampard does not expect to have the France midfielder back until March.
"N'Golo is not fit, he has a muscle injury, similar to the one he picked up against Arsenal; hopefully three weeks, something around that," Lampard told reporters.
Kante's absence is a blow for Chelsea as they head into a crucial period featuring this weekend's showdown with top four rivals Tottenham and Tuesday's Champions League last 16 first leg against Bayern Munich.
Chelsea also have an FA Cup fifth round date with Liverpool on March 3 and Kante will not be back for that.
The 28-year-old has had a host of injury problems this season and as a result he has been restricted to 16 Premier League starts.
Chelsea will slip out of the top four if they lose to Tottenham at the Bridge and with Kante out, Lampard was relieved to be able to welcome back England midfielder Ruben Loftus-Cheek.
Loftus-Cheek tore his Achilles tendon in April and the 24-year-old is likely to feature from the bench for the first time in Lampard's reign.
"Ruben is in the squad, he's not fit to start but it's great to have him in the squad," Lampard said.
Adding to Chelsea's walking wounded, Danish defender Andreas Christensen will wear a protective mask against Tottenham having broken his nose against United.
"Andreas went to get a mask for a broken nose that he's now trained with, so he's available for selection, albeit with wearing a mask," Lampard said.
Tammy Abraham is another Chelsea star struggling with injury, with the England striker still battling an ankle issue suffered in last month's draw with Arsenal.
"Tammy has trained the last two days but he's probably at about 70 percent and he hasn't trained much recently," Lampard said.
Meanwhile, Lampard insisted there is no tension with Chelsea's board over his decision to drop Spain goalkeeper Kepa Arrizabalaga.
Kepa cost a world-record transfer fee for a keeper when he joined Chelsea for £72 million in August 2018.
The 25-year-old has fallen out of favour at Stamford Bridge, though, with veteran Willy Caballero stepping up for the last two Premier League matches.
Reports suggested Chelsea's hierarchy were unhappy with Kepa's demotion but Lampard said: "Certainly not. That fills a lot of headlines for people.
"I'm absolutely together with all the club and the board, because we all want the best. And I'm paid to make decisions.
"So with form I have to consider the goalkeeper position. Recently it's just changed, but that's nothing final."