DELRAY BEACH, Florida (AFP) -- German second seed Tommy Haas continued his good form from last month's Australian Open as he reached the ATP Delray Beach quarterfinals with a round-robin triumph here Thursday.

Haas, who returned to the top 10 for the first time in four years after reaching the semifinals in Melbourne, beat American Sam Querrey 6-4, 7-5 to join seeded compatriots Florian Mayer and Benjamin Becker in the final eight.

Fourth-seeded Becker defeated American Jesse Levine 6-3, 6-3 to punch his quarterfinal ticket.

Germany's Rainer Schuettler, however, failed to advance, despite posting a 6-7 (4/7), 7-6 (7/1), 6-3 victory over third-seeded Belgian Xavier Malisse.

Their group, which also included Colombian Alejandro Falla, finished with all players standing on one win and one defeat. Malisse advanced by virtue of winning more total sets.

Top-seeded American James Blake didn't need any complicated calculation to book his quarterfinal berth.

He needed less than an hour to wrap up his second straight round-robin victory, 6-1, 6-3 over compatriot Scoville Jenkins.

U.S. eighth seed Vince Spadea, unseeded Italian David Sanguinetti and Spanish seventh seed Guillermo Garcia-Lopez advanced.

Spadea downed compatriot Ryan Sweeting 7-5, 6-4 and Sanguinetti ousted American Amer Delic 6-3, 4-6, 6-3 to reach the knockout phase of the 416,000-dollar event.

Seven of the top eight seeds advanced from the round-robin.