Andriy Shevchenko concedes it has been a "difficult season" for former club Chelsea but believes tonight's clash with Barcelona could "change everything".
The west Londoners have endured a turbulent campaign on and off the field, although they have progressed to the last four in Europe and face Barca in their first-leg tie tonight.
Chelsea also have an FA Cup final date with Liverpool to look forward to and Shevchenko has backed his former team-mates to end the campaign on a high.
"I would say it has been a very difficult season for Chelsea," said the Ukraine international, who was with the Blues between 2006 and 2009.
"It is not finished yet and only one [English] team is playing in the Champions League still, which is very good for Chelsea.
"Maybe Chelsea can play in the final. You never know.
"Of course they are not in a good position in the Premier League because I think Chelsea always fight to win the league.
"Now they also need to think about the Champions League but in football when the season has not finished, you cannot say it is a bad season.
"I think Chelsea can change everything in one game.
"If Chelsea beat Barcelona and play well, of course there is another game after that, they will have a good chance to play in the final.
"Barcelona is a great team with great players and has played fantastic football. They have a lot of possession and are good at finishing.
"Chelsea, though, always have a good chance at home because they have supporters that push the team in a good way to win the game.
"I think Chelsea have a chance because the last couple of games they have played very well.
"They beat Tottenham in a very important game and all my old partners' experience of European football will help.
"Frank Lampard, John Terry, Didier Drogba, as well as the young players and [Branislav] Ivanovic."
Chelsea have enjoyed an impressive turnaround in recent months since Roberto di Matteo was installed as interim manager in place of Andre Villas-Boas.
Shevchenko, who now plays for Dynamo Kiev, praised the Italian for his work at Stamford Bridge, but was coy on whether he should get the job past the end of the season.
"I think the owner will decide, but I think Roberto di Matteo is doing a great job," he said.
"He has had some good results, like Napoli where Chelsea played very nice. I don't know who I want as boss, it is not my decision.
"I think Di Matteo has a good opportunity to show everyone how good he is and maybe [persuade] the Chelsea owner with a good result he should stay in the job."