Harry Redknapp has backed Graham Potter to be a success at Chelsea once the former Brighton and Hove Albion boss has his best players available.
Potter is enduring a difficult time at Stamford Bridge, with Chelsea having lost six of their past eight games.
The Blues have won just once during that poor run, beating Premier League strugglers Bournemouth 2-0 at home on December 27.
Sunday's 4-0 defeat to Manchester City in the FA Cup served up a stark example of the gulf between 10th-placed Chelsea and teams battling for the title, yet Redknapp insists Potter, who replaced Thomas Tuchel in September, simply needs time to get to work.
Chelsea's injury list is a long one, with Reece James, Ben Chilwell, Wesley Fofana, Christian Pulisic, N'Golo Kante, Ruben Loftus-Cheek and Edouard Mendy the first-team regulars out of action.
"You can't sack the lad can you, he's not been there 10 minutes – he's got a million injuries you know, you've got injuries galore, both his full-backs, Chilwell, James, important players, Fofana came in unfit, they've got lots of injuries," Redknapp told Stats Perform.
"They have still got a very, very strong squad. They've spent money like it's going out of fashion but he needs time. He's only as good as your players at the moment – it's not rocket science. People seem to think you go in and show them how to play football. It doesn't work like that.
"At the moment, he's got his best players missing and they're struggling to win. When they get back in the team, you'll see a massive improvement."
Chelsea have been active in the January transfer window, signing four players already, while they are also eager to land Benfica's World Cup star Enzo Fernandez.
While that transfer appears to be on ice for now, the Blues confirmed the loan signing of Joao Felix from Atletico Madrid on Wednesday.
Redknapp does not think more signings are necessarily a silver bullet, however.
He said: "They've got enough players, they just need those back from injury – they need James back, they need Chilwell back. There's no reason they can't go on a run."
Potter has won eight of his 18 games in charge at Chelsea (44.4 per cent), and Redknapp says it would be foolish for the club to show him the door.
"Five years – you just gave him a five-year contract, you can't very well bring him in, give him a five-year contract and then sack him, surely to God," Redknapp said.
"I know they've done it before, Chelsea, that is the way they've worked. Managers who've won the Champions League and then they've been sacked a couple of games later, it happens. But I don't see that happening this time."