Del Potro Ousts Ginepri at ATP Tokyo

"I served very well today and that took pressure off me," said del Potro. "[Ginepri] gave me a couple of opportunities and I took them. I like to play on these courts, hard is my favorite surface."

The 18-year-old del Potro, who reached the Umag quarterfinals in July and has won two ATP Challenger circuit title in Aguascalientes and Segovia this season, will next meet No. 10 seed Tim Henman, who spanked Canadian Frank Dancevic 6-2, 6-1.

"I was playing against Henman on the PlayStation last year and now I meet him for real on a tennis court. I am looking forward to that," said del Potro.

Germany's Lars Burgsmuller needed three tiebreaks to get by big-serving Wayne Arthurs 6-7(5), 7-6(7), 7-6(3). Burgsmuller will now meet the No. 5 seed Jarkko Nieminen.

Also posting wins on the second day of play were Stefan Koubek, Alexander Waske, Danai Udomchoke, Rainer Schuettler and Satoshi Iwabuchi.

Top seed Roger Federer will be in action Wednesday as he takes on Serbian Victor Troicki in the second round. Troicki, a 20-year-old winner of one ATP Challenger circuit title in Dharwood this year, won his first career tour match over Spain's Fernando Vicente 6-7(4), 6-4, 6-2.

"I am really very excited," said Troicki of visiting Club Fed. "I am going to go out there and try to play my best tennis. I will try to stay calm and focused. I often watch him on TV and he's getting better and better."

Second-seeded Tommy Robredo meets Yen-Hsun Lu and No. 3 seed Mario Ancic will clash with Kenneth Carlsen.