Di Maria struck the only goal of the game in the 1-0 Champions League win.
He said: "I'm very happy with my goal and with our victory at a complicated venue. It looks like its complicated to win away matches in the Champions League this season and we took three essential points. It was important to win and we did. I'm very happy.
"I scored a beautiful goal thanks to receiving a great pass from Marcelo. I'm very happy because I'm doing a good job. I work to improve every day.
"We think only of ourselves. We must be calm, knowing things will go well for us if we carry on this way. This has only just started. We're happy with how things are turning out, but we have to take things slowly."