“You’ll see some changes,” said the 33-year-old, who must decide whether to recall Fernando Torres to his attack and who will replace the suspended Ramires in midfield. “Then we’ll make wise decisions for Sunday.”

Didier Drogba will once again miss out tonight as he continues his recovery from a head injury.

The striker was given another two days off this week and is looking more and more likely to sit out Sunday’s trip to Old Trafford.

Torres appeared a strong favourite to continue his run in the team before he lost his place for Saturday’s win at Sunderland and the misfiring striker’s misery deepened yesterday when it emerged Chelsea were probing an interview he gave in which he appeared to criticise his own teammates.

The Spain forward claimed his comments were mistranslated, even though they appeared on his personal website.

Torres was bought to help Chelsea win the Champions League, with Villas-Boas ultimately recruited for the same reason.

The Portuguese has yet to manage in the competition but has plenty of experience of it from his time on Jose Mourinho’s coaching staff.

History shows it can be vital for a team to win their group to go on and lift the trophy, but Villas-Boas said: “The competition is full of exceptions. I lived Porto’s experience and we managed to play all the second legs away from home and still qualified to win the Champions League in 2004.”

Tonight’s game will reunite Villas-Boas and Chelsea with former Stamford Bridge midfielder Michael Ballack.

Villas-Boas said: “I haven’t been able to speak to Michael for a lot of years, since I left. He’s a player who represented a lot to us and represents a lot to Leverkusen.

“I’m not sure about the thoughts of their coach regarding Michael’s inclusion in the squad, because they’ve been using him sometimes and other times not. But he adds value to the squad with the vision he has.”

Ballack returned the compliment about the former Blues scout, who is a year younger than him.

The veteran midfielder said: “In my time at Chelsea I had a few coaches and sometimes they changed them maybe a little too quick, but what is surprising is he is a very young coach.

“When people talk about him, they talk most of the time about his age but he showed his quality when even in this young age he won a European trophy with Porto, which is unusual.

“It is not surprising that Chelsea always had their eye on him, he worked there before in the background and he did a lot of important stuff for Jose Mourinho.”