Tennis: DelPo says world no.1 is main motivation

Argentina's Juan Martin del Potro warned that he was ready for an assault on the top of the world rankings after winning his 16th career title at the Japan Open.

Looking down the list of tennis greats engraved on the trophy, the former US Open champion told AFP: "Amazing names. When you win this kind of tournament it means a lot."

Del Potro voiced confidence his victory in Tokyo at the second bite of the cherry -- he was a beaten finalist in 2008 -- would act as a springboard for a strong end to the season.

"This is a big tournament," he said in an interview, after beating Canada's Milos Raonic 7-6, 7-5 in the final.

"I played really well, beating fantastic players. It's fantastic for me to win this title and now I'm very excited to keep improving my game because I want to get closer to the top guys."

The towering 'DelPo' took full advantage of being handed a wildcard to play his first event since a shock second-round exit at last month's US Open, adding to victories in Rotterdam and Washington earlier this year.

He moved up from sixth to fifth in the Race to London standings for the season-ending World Tour Finals and is also projected to rise from seven to five in the new ATP rankings.

Asked about becoming a consistent threat at the four Grand Slams and joining the world's elite, he said: "I believe in myself for sure. I'm working hard to improve. There is no bigger motivation than becoming number one in the world."

Del Potro's breakthrough at the 2009 US Open, where he beat Rafael Nadal in the semi-finals before toppling Roger Federer in the final, hit the rocks after he underwent wrist surgery the following year and missed eight months of the 2010 season.

"I beat these guys in the past and I know if I'm healthy, if I'm playing well I will have the chance in the future to beat them again and get closer to them in the rankings," said del Potro, who pushed Novak Djokovic to the limit in this year's Wimbledon semi-finals.

"I was close to beating Djokovic at Wimbledon," he said of his 7-5, 4-6, 7-6, 6-7, 6-3 defeat, the longest semi-final ever at the London grand slam at four hours, 43 minutes.

"I just have to be fit and healthy."

A respiratory virus forced del Potro to pull out of this year's French Open before he returned with a vengeance in London but his performances in Tokyo, and consequent rise in the rankings, point to a stirring finish to the 2013 season.

Reading the names of former Japan Open winners -- from Ken Rosewall in 1973 to four-times winner Stefan Edberg and also including John McEnroe, Pete Sampras and recently Federer, Nadal and Andy Murray -- del Potro let out a sigh of satisfaction.

"It's a really difficult tournament to win," he said, pointing out with a grin that his own name had yet to be engraved on the silverware.

"If I stay fit and my serve and forehand are working good too, who knows what I can do? I will keep believing in myself and look forward to improve my game for the future."