Dominic Thiem says he's surprised even himself with his run during the South American swing.

The 22-year-old won a title and a reached a semifinal in two South American clay events, then won his first hardcourt title at Acapulco, defeating Bernard Tomic in three sets in the final.

"It was unbelievable," Thiem was quoted as saying on the ATP website. "These three weeks have been amazing. Winning my first 500 title and first hard-court title, it was just perfect. It was how a final should be... between two young and up-and-coming players."

Thiem also had some big wins along the way, defeating Rafael Nadal and David Ferrer. He will rise further into the top 15 with his Acapulco win.

"I started to play very well already in Buenos Aires, and I'm a little bit surprised that I could keep this run so long," he said in an on-court interview following the semifinal.

The Austrian is 18-4 for the season.