Belief is the key, according toAncelotti, who led his team to victory at Old Trafford a year ago,albeit when confidence was soaring amid a run of nine wins from 10games.
Twelve months on, the Blues are not thesame force. They spluttered to a 1-0 win against Wigan on Saturday andthe manager does not appear to know the best way to accommodateFernando Torres, but Yossi Benayoun insists they can still win theChampions League if they fight back to beat United.
Back with a bang: Benayoun (right) impressed on his return to the Blues fold after a injury lay-off
'The manager, the players, everyone knows we are playing to save our season,' said Benayoun, back from injury against Wigan.
'From here, it's most likely we'll finish in the top three or four and be in the Champions League next season. That's almost done. The only thing left is to try to win a trophy and the only trophy we can win is the Champions League.
'If we win this game, it will change everything. I'm sure that if we beat United we'll go to the end and win the trophy. It is our final.' Chelsea must overturn a 1-0 deficit from the first leg. Only twice have teams progressed in the Champions League after losing at home in the first round of a knockout tie.
'People think they're almost through because they won away,' said Benayoun.
'It was an important goal but when you play English team against English team, I don't think the away goal is as much of an advantage as it normally would be in Europe.
'It's1-0, a small advantage, because we have proved we can score at Old Trafford. Normally, they like to attack at home but they might stay a bit deeper to protect the lead. This might work better for us.
'Uniteddeserve respect. They're a big team but we have the belief we can do it. We can win there.' Benayoun's return may be significant, even if the30-year-old Israeli suspects he is not ready to play 90 minutes after six months out with an achilles injury.
Therewere glimpses against Wigan that he is on a wavelength with Torres, an understanding forged when they were room-mates at Liverpool. Ten games into his Chelsea career, Torres is still without a goal, but at least helooked more of a threat with Benayoun darting behind.
Wigan boss Roberto Martinez expects his fellow Spaniard will prove 'a bargain' buy, even at ?50million.
'It is hard to get used to his game,' added Benayoun.
'Chelseaare used to playing with Didier Drogba, so that means playing up to hisbody, not playing behind the defenders into space, which is where Fernando wants the ball. I know where he wants the ball.
Best of mates: Benayoun linked up well with Torres (right)
'Slowly,slowly, the players have got to know him better. He's making the right movement and he's been unlucky. Like any striker, if you miss a few chances, you lose a bit of confidence. But as soon as he scores one, I can promise you, he will be the top scorer.
'For me, he's the best striker in the world. He will score a lot of goals and you will see the best of Fernando.'
Benayoun's jinking dribble and disguised pass created a gaping chance for Torres in the 89th minute against Wigan, only for keeper Ali Al Habsi to respond with an incredible save. Torres turned to his former Liverpool room-mate and broke into resigned laughter.
'It was a great save, like the keeper had an extra hand to save it,' said Benayoun.
'Fernando was smiling and joking, saying, 'I don't know what to do, how could I not score with that?'
'But I knew it was just a good save. His first goal will be the most important and hopefully it will come at Old Trafford.'
Ancelotti rested players on Saturdaywith tomorrow's game in mind. John Terry took a breather, MichaelEssien spent the afternoon watching from the bench and Torres came onfor the last half-hour.
Alexand Benayoun returned after longterm injuries. David Luiz is ineligiblein the Champions League and Jose Bosingwa, who has been unwell, will beassessed to see if he can travel to Manchester, but the big selectiondilemma is likely to be over the partner for Torres up front, Drogba orNicolas Anelka.
Ancelotti left Stamford Bridge on Saturday with plans to study the DVD of last week's defeat by United.
'I will watch it two or three times,' said the Italian. 'I want to try to do something special for the next game.'
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