Chelsea star Juan Mata insists they're capable of upsetting Champions League opponents Napoli.

The Blues must overturn a 3-1 deficit at Stamford Bridge.

"In football, nothing is impossible," the 23-year-old said. "At Stamford Bridge, this Champions League, we had good results in the group - 3-0, 2-0 and 5-0.

"All the supporters, for sure, will be cheering us. It's a final for us and I think we can do it."

Napoli's strengths and weaknesses were laid bare during their 6-3 Serie A win over Cagliari on Friday night.

Mata added: "From the first minute, we have to try to create chances to score. We know that they have very, very good strikers.

"We have to be careful with them but we are going to press them from the first minute."