INDIAN WELLS, CALIFORNIA // Juan Martin del Potro's superb comeback from injury gathered further momentum last night when he beat defending champion Ivan Ljubicic 5-7, 6-4, 6-2 at the Indian Wells ATP tournament.
The Argentine, who played just three tournaments last year because of an injury to his right wrist, lost a tight opening set before breaking his higher-ranked Croatian opponent once in the second and twice in the third.
"I feel bad I beat the last champion, and of course a nice victory for my comeback," del Potro, the former US Open champion, said after advancing to the third-round, where he will meet Alexandr Dolgopolov.
"I played good tennis. I was focused all the match on trying to take my opportunities. I think I played better than him, and that was the key of the match."
Del Potro, who has slipped to 90th in the rankings from a career-high fourth, was delighted to see continued improvement in his form.
"I'm playing much better," said the 22-year-old, who won his eighth ATP title at last month's Delray Beach International Championships.
"I have improved my forehand, my serve, my physical condition, everything. It's easier when you win a match. You can improve very fast if you still play [in tournaments] and are still winning."
Del Potro, who reached successive semi-finals in San Jose and Memphis before winning the Delray Beach title, said he had stayed patient throughout his injury comeback.
"I'm very calm with my level," added the Argentine, who rocketed from 484th in the rankings to 90th in a three-week span. "I know that it's a long road to be at the top again, but I'm working.
"I have the game — if I'm healthy. I need time to improve, to work hard. Maybe in a couple of months, maybe next year, I will be ready to play against all of the top players."
Del Potro has won seven titles on the ATP World Tour, including the 2009 US Open.