Basel, Switzerland: French Open champion Stan Wawrinka suffered his eighth first-round defeat at the Swiss Indoors on Wednesday when he slumped to a 3-6, 7-6 (7/2), 6-4 loss to Ivo Karlovic. Karlovic, the 36-year-old Croatian, sent down 21 aces to take victory over the Swiss second seed after trailing a set and a break. "I had a poor first set and was missing a lot with my volleys," said Karlovic.

"But I began improving in the second set and got a bit lucky when I converted my break points (in the sixth game at 3-3). After that, things started going my way." Karlovic, who had lost five of six previous meetings with Wawrinka, next plays Serbia's Dusan Lajovic. Wawrinka was disappointed to have let the match slip away.