Summary:
World number one Juan Martin del Potro suffered a heavy defeat on his comeback at the Japan Open, losing in straight sets to Feliciano Lopez.

Full article:
(CNN) -- Juan Martin Del Potro is confident he can return to his best form in a month after crashing to a 6-3 6-0 defeat against Spain's Feliciano Lopez in the first round of the Japan Open. Del Potro is still working his way back to full fitness after an eight-month absence with a wrist injury, and world number six Lopez took just 82 minutes to dispose of the Argentinean. Speaking to the ATP World Tour website, the 22-year-old said: "It is difficult to come back and play against these players, especially Feliciano on such a fast court. "I need time, I need to work on a few things to get back to my best level. If I work in a good way, I will be in good shape in a month or so." Elsewhere in the draw, Russia's Dmitri Tursunov earned an impressive win over seventh-seed Ernests Gulbis, defeating the Latvian in straight sets 6-3 6-4. Tursunov did not suffer one break of serve in the match, completing his victory in a swift 72 minutes. On the women's tour, Jelena Jankovic suffered a shock defeat at the China Open, going down 6-2 2-6 6-2 against fellow Serb Bojana Jovanovski. It was a disappointing result for the third seed, who exited in the second round alongside Agnieszka Radwanska. Radwanska lost 5-7 7-6 7-5 in a hard-fought match against Angelique Kerber of Germany.