Second seed Andre Agassi and defending champion Tommy Haas were upset in the quarter-finals of the 380,000-dollar ATP US Clay Court Championships here on Friday while top seed Andy Roddick advanced. French sixth seed Sebastien Grosjean advanced by ousting American star Agassi 4-6, 6-1, 6-2 while seventh seed Jurgen Melzer of Austria dethroned Germany's Haas 2-6, 6-2, 6-4.
Roddick, who won here in 2001 and 2002, advanced to a semi-final matchup with Melzer by beating Peruvian eighth seed Luis Horna 6-4, 6-1.
Roddick, who has not lost a set this week, has won 21 of his first 25 ATP matches this season. He seeks his second title of the year after winning in February at San Jose.
Agassi, one week shy of his 35th birthday, was bidding for his 60th career title in his fifth quarter-final of the year. He has yet to reach a final.
COLLATED RESULTS (denotes seed):
(Quarter-finals): Jurgen Melzer (AUT x7) bt Tommy Haas (GER x3) 2-6, 6-2, 6-4; Andy Roddick (USA x1) bt Luis Horna (PER x8) 6-4, 6-1; Sebastien Grosjean (FRA x6) bt Andre Agassi (USA x2) 4-6, 6-1, 6-2; Nicolas Lapentti (ECU) bt James Blake (USA) 6-4, 1-6, 7-6 (7/3).