"Yes, we are, we are," he said.
"A lot of good teams like Tottenham, Arsenal, Man United played in European tournaments but now we are going to play in the Champions League final, representing England as well."
However, Mata acknowledged Chelsea's performances have been up and down.
He said: "We won the FA Cup. It's true that in the Premier League, it hasn't been an easy season for us.
"But now we have the chance to play in the Champions League next year by winning the trophy, so it will be amazing for us to win it."