Chelsea take on Porto at the Estadio do Dragao on Wednesday night with Ivory Coast striker Didier Drogba among the substitutes.

Ancelotti will ring the changes from the team that demolished Wolves in the Premier League on Saturday, with Deco, Ricardo Carvalho and Michael Ballack all back in the side - but the Italian coach does not underestimate the challenge awaiting his side.

Porto have lost just once in Europe this season - a 1-0 reverse at Stamford Bridge where a Nicolas Anelka goal proved decisive.

They, like Chelsea, have only conceded two goals in Europe and victory for Jesualdo Ferreira's side will give Porto the edge going into the final group game.

It is very much a pressure game for Ancelotti and his Chelsea side, who have failed to sparkle on their travels in Europe this season.

A 1-0 victory over Apoel Nicosia, again thanks to an Anelka strike, was followed by a 2-2 draw against Atletico Madrid. But the dreary performances in both games was hardly the stuff to drive fear into Porto's hearts.

But then fear is something not contained in Ancelotti's mindset either.

"Porto have a very good team and coach but while we respect them we have no fear," said Ancelotti.

"I think tomorrow is important not only for first place, but we will play against a strong team. They did well in the last game at Stamford Bridge. We want to put our personality and quality on the pitch tomorrow night.

"We want to arrive at first place in the group and it is a very good test because Porto are a very good team.

"We have the possibility to win if we play better than them. I don't know any other way."

Team selection was a major topic on the agenda ahead of the game and although Ancelotti stopped short of announcing his line-up, it was not hard to fill in the gaps.

"We are in Portugal and Carvalho and Deco will play," said Ancelotti. "I want to change some players. The players who did not play against Wolves will play tomorrow. Branislav Ivanovic, Deco, Ballack, Carvalho.

"I don't know about Drogba. Maybe he will start from the bench. He is well but I prefer to keep him on the bench.

"Essien has a little problem on his knee. I prefer to keep him on the bench but it will not be a problem for Sunday against Arsenal.

Ashley Cole is also out with Yuri Zhirkov drafted into the left-back spot.