Chelsea manager Thomas Tuchel said his players must not "lose their heads" by allowing their 2-0 first-leg advantage over Porto in the Champions League quarter-finals to lull them into a false sense of security heading into Tuesday's return.
"We don't approach games like this, to talk about the result we have and then change our approach," Tuchel told a news conference on Monday.
"It's important to be fully focused and play the best game possible.
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"It's easier for Porto to adapt because they know what they need to do to go through. For us if we start adapting we could easily lose our heads.
"What does it mean? Is it enough to lose one-zero? Why should we enter this frame of mind? We have a certain way of playing and we will try to bring that. We have to be free in our minds to react to situations on the pitch."
Chelsea face a defining week with an FA Cup semi-final clash against Manchester City at Wembley on Saturday. Tuchel believes his side are on course for a strong finish to the season.
"There's nothing less interesting than the past," he said. "Everything that counts is the next match and competition.
"Tomorrow there's no trophy to win, on Saturday there's no trophy to win, but these are matches where we can take decisive steps."
N'Golo Kante, who has struggled with a hamstring problem in recent weeks, is available for the game, but Tuchel said he would take a late call on the France midfielder.
"We need to be careful about him," the German added. "The question is whether we want him to start or finish the game. It is not answered yet, I will do this tomorrow."
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