Tokyo, Japan -- (Sports Network) - Fifth-seeded Argentine Juan Martin del Potro rolled to a semifinal win on Saturday, while No. 2 seed American Andy Roddick was eliminated by ninth-seeded Czech Tomas Berdych at the $869,000 Japan Open Tennis Championships.

Del Potro, fresh off an upset of top-seeded Spaniard David Ferrer in the quarterfinals, defeated fourth-seeded Richard Gasquet of France 6-3, 4-6, 7-5. The fifth seed saved 7-of-9 break points and used six aces in the third set to come away with the victory.

Del Potro, who turned 20 years of age on September 23, is making a quick rise in the top 10 of the world. By winning the Tokyo title he can overtake James Blake at No. 8. The victory Friday was Del Potro's 29th in his last 30 matches.

Gasquet failed to advance to his second straight Tokyo final. He lost to Ferrer last year.

Berdych, meanwhile, needed two tiebreakers to win in three sets over Roddick 6-7 (3-7), 7-5, 7-6 (7-3) and keep alive his hopes for a fourth career title, and first since Halle in 2007.

Neither serve was broken in the first set, but Roddick took over in the tiebreak to take the early edge. Berdych answered and broke Roddick's serve while knotted at five games apiece in the second set before evening the match.

The Czech came back to take the tiebreak and the third set, though, to send Roddick packing. Roddick was trying for his fourth title of the year and second in a row, having captured the Beijing crown last week.

The 2008 Tokyo champion will collect $135,000.