The Blues take a 1-0 lead into the second leg thanks to Salomon Kalou’s second-half winner at the Estádio da Luz last week.
But the interim Chelsea boss says his side can take nothing for granted against the Portuguese side – and insists there has been no talk of a potential semi-final clash with either AC Milan or Barcelona.
“This tie is far from over,” he told a news conference on Tuesday. “They [Benfica] have scored in every away game in the Champions League this season so we know that it’s a difficult task ahead for us tomorrow night and we’ll have to approach this game like the Napoli game.”
Reflecting on his side’s improved form since he took charge from André Villas-Boas, Di Matteo added: “It’s important for us to perform in every game and we are pleased that the wins come with good performances. Tomorrow we have to produce a great performance to be able to overcome Benfica.
“I think the fact that we are winning games helps to improve the confidence within every individual player and the group.”
The 41-year-old Italian also moved to allay fears over a congested fixture schedule as the season reaches its climax – and confirmed that all of his squad were fit to train on Tuesday evening.
“I think there’s a lot of clubs that would like to have so many games and be involved in all these competitions,” he said. “We have to try and keep going and try to stay in these competitions and try to win something.
“It’s very demanding for the players but fortunately at the moment because all the players seem to be available, so that will help us.”
• Chelsea have made Stamford Bridge something of a fortress on Champions League nights this term. With their 4-1 comeback win against Napoli in the last round, the London club have now recorded four straight victories and scored 14 goals with just one conceded.
• Including last season, Chelsea have suffered just one defeat, against Manchester United in the 2010-11 quarter-finals, in their last nine home fixtures in Europe.
• Benfica have already got the better of one Premier League side in this campaign, having earned two draws with Manchester United as they finished top of their group with the English champions down in third place.
• Benfica have appeared in 15 European Cup quarter-finals, winning eight and losing seven – including all three against English sides.
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