Jose Mourinho doesn't know what his best Chelsea team is, says Jamie Redknapp.
The Blues boss accepted responsibility for his side's shock 2-1 defeat to Basel in their opening match of the Champions League - their first home defeat in the group stage for 10 years.
Mourinho still expects Chelsea to advance to the knockout stages - they travel to Steaua Bucharest next - but Redknapp told Sky Sports that he must settle on a first-choice line-up and formation to achieve that goal.
"If it wasn't Jose Mourinho, you'd probably be thinking 'what is this guy up to? What's their best system? What's their identity? How do they play?'
"I've seen him use so many players in different positions since the start of the season. I still can't believe he's not picking Juan Mata. When I think about Chelsea retaining the ball and people who are comfortable on it, Mata has to play.
"I just think at the moment there's no real system to the way that they play. Where's Andre Schurrle? Where's Kevin De Bruyne? I don't think Jose really knows what his best team is.
"When you play football, it's about building relationships - be it centre-backs, midfielders, wide men, front men. At the moment, no-one seems to have any relationship with anyone because they don't know who he is going to play."
Oscar gave Chelsea the lead just before half-time at Stamford Bridge only for Mohamed Salah to equalise before Marco Streller gave the Swiss side victory with nine minutes remaining.
Sky Sports pundit Jamie Carragher admitted the winner - a near-post header from Matias Delgado's corner - was a poor goal to concede but insisted that Chelsea's problems stem from their lack of attacking clout, rather than the absence at the back of John Terry.
"I think there's a lot more to it than just the absence of John Terry," he reflected. "Virtually every game I've seen Chelsea in, they are playing with 10 men.
"They haven't got a centre forward, have they? He's tried them all - he's even tried going with no striker at Old Trafford. He's tried everything and it just doesn't work.
"No matter how many players you've got, if you haven't got a centre forward - a top striker - a lot of it falls down. At the moment, it's like they are a man down before they start the game.
"This Chelsea team is totally different from the one he had - it seems to lack power, energy. Your Hazards, Matas and Oscars are quality players but when you watch them, it's like they get out-powered in the second half. They seemed second to every ball, especially in midfield."
Redknapp agreed that a lack of firepower - and focus - up front was undermining Chelsea's start to the season, comparing the current squad to the one that won back-to-back Premier League titles under Mourinho in 2004-05 and 2005-06.
"Mourinho built his success at Chelsea on Didier Drogba - he was the focal point of the team. But Samuel Eto'o floats out to the left, he floats out to the right. That gives you no-one to play off.
"I know what Drogba did is history but I still believe you need someone up there. They've got so many players who keep wanting to come inside that I don't see any width.
"No-one wants to run without the ball - everybody wants the ball to feet. I couldn't believe the performance that Eden Hazard put in. He should be lighting the place up.
"I thought he'd be really flourishing under Jose but he was so disappointing. I didn't see him go past the full-back once."
Michael Ballack, who made 167 appearances for the Blues between 2006-10, said that this Chelsea team is still evolving and that it will take time for Mourinho to strike the right balance in terms of style.
"The crowd at Chelsea accept a certain kind of football - a powerful style of football," he said. "I saw a typical Chelsea situation in the 91st minute when Mikel chased the ball; he won the first challenge, got the ball and then they attacked with three or four players in three or four seconds and they had a chance.
"That was Chelsea. Now they have smaller players who are outstanding talents but they lose a lot of balls; the balance between fighting defensively and offensive football is not right at the moment.
"It's disappointing for Chelsea, especially when you see the way that they played. Basel deserved the victory 100 per cent.
"They didn't really believe in themselves at the start but the longer the game went on, they believed more and more and then they got more chances. They scored two fantastic goals and they deserved it."
Chelsea's next game is against Fulham at home in the Premier League. You can watch it live on Saturday Night Football from 5pm on Sky Sports 1.
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