The Argentine scored a vital goal five minutes from time in the first leg at Camp Nou, and he believes that his side can push the Catalan giants all the way in the return fixture
The result leaves the Catalan giants taking a slender one-goal advantage into the return leg, but with the scoreline finely poised, the winger, who scored a crucial second for his side, is backing his side to overturn their deficit at the Santiago Bernabeu.
"The result is not good for us, but we are calm. Playing at home, with our fans behind us, we will do everything possible to win the match and the trophy," Di Maria told the club's official website.
"We knew what we were facing, Barcelona always play the same way and we wanted to play the game that we have played in recent visits to Camp Nou.
"We played until the end, and we were rewarded and have kept ourselves in the tie."
Jose Mourinho's men welcome Barca to the capital for the return leg next Wednesday evening, with both teams returning to Liga action at the weekend.