It’s a perfect dozen for Juan Martin del Potro…

The 24-year-old Argentine professional tenista , currently ranked No. 8 in the world, won his 12th career title on Sunday, beating qualifier Grega Zemlja of Slovenia 7-5, 6-3 at the Erste Bank Open.

It’s only the second indoor title for “Delpo,” who earned the bronze medal in men’s singles at the 2012 Olympic Games in London.

del Potro, the top-seed at the Austrian event, was playing his first tournament since returning from a right wrist injury that sidelined him for more than a month.

“It’s been a fantastic week,” said del Potro. “Coming back to the tour and being seeded No. 1 put me under pressure. I am so happy now. Winning a tournament means a lot. It’s important to have a good end to the year.”

del Potro improved to 12-5 in finals and is a strong favorite to pick up one of the remaining berths at the season-ending ATP World Tour Finals.

“That was on my mind coming here,” he said. “I am looking even better now … but I still have two big tournaments and must do well in Basel and Paris.”

A losing finalist last year, del Potro survived a shaky start against the 70th-ranked Zemlja, who was the first player from Slovenia to reach a final after upsetting Janko Tipsarevic in the semifinals.

At 2-2 in the opening set, del Potro lost serve for the first time in the tournament. But from 2-4 down, he won 11 of the next 15 games to close out the victory.

“It wasn’t a good start, I was nervous because it was a final,” said del Potro. “In the second set, I broke him early and that gave me confidence to play the final like everyone expected me to do.”