Andre Villas-Boas can succeed at Chelsea, says Graeme Le Saux

Former Chelsea player Graeme Le Saux says he hopes under-pressure boss Andre Villas-Boas can be a long-term success.

Chelsea have not won in their last four games and face a tough trip to Napoli on Tuesday night in the first leg of their last-16 Champions League clash.

"I hope Andre is there for many years to come and he gets the chance to really establish himself," ex-England defender Le Saux told BBC Sport.

"He is young and talented and shouldn't be written off after one season."

The 34-year-old former Porto boss took over at Stamford Bridge in June after Carlo Ancelotti was sacked.

But with Chelsea fifth in the Premier League, trailing leaders Manchester City by 17 points, there has been speculation the Portuguese could be sacked if his side are knocked out of the Champions League by the Serie A team.

He was even forced to reject suggestions that influential forward Didier Drogba gave a half-time team talk in Saturday's 1-1 home FA Cup draw against Championship side Birmingham.

Le Saux says Chelsea's players, including those who are not regularly starting matches, need to demonstrate the right attitude.

"The most important thing is they show a unified front when they do play and that they support the manager through what is a time of difficult decisions," said Le Saux, who is a club ambassador.

"Due to a few inconsistencies, as well as injuries, he's had to use many players and sometimes out of position, which doesn't help the continuity and team spirit."

Villas-Boas won four trophies at Porto, including the Europa League last year, and Le Saux believes he has the potential to be a winner at Chelsea.

"I was away working with the club when Andre first took over and my first impressions of him were very, very positive," he said. "He's a tactician, very well organised, and very disciplined in his approach.

"Chelsea have had a poor season domestically and that is something people have used as a reason to let him go.

"My own personal belief is that if you've invested in somebody and the potential they have, you have to give them a good chance to show their potential.

"I just hope the powers-that-be at Chelsea continue to keep faith in him and his principles and he gets the opportunity to continue the process of what he's started in terms of getting the squad into a position where they can achieve again.

"The reasons they brought him into the club haven't changed. Results in the league have been inconsistent and by Chelsea's very high standards, probably not good enough, but there has to be a longer term objective."

Former Chelsea and Scotland winger Pat Nevin says Villas-Boas should be given at least two years to build a squad at Stamford Bridge.

"It would be desperately unfair on him if he wasn't given the time. I know a lot of people feel as if he won't be given the time but I think that would be a real sadness if he wasn't," he told BBC Sport.

"It may be AVB needs two years, gets two years and still can't do the job but if once again Chelsea do decide to get rid of the manager very quickly it is going to be extremely tough for anyone coming in.

"A whole raft of different managers bought those players. How can your organise a structure going forward if it's all been put together in such a piecemeal way? Eventually, someone has to be given time to do it."