KEY BISCAYNE, Fla. (AP) -- For the first time since 1999, Andre Agassi will head into the clay court

KEY BISCAYNE, Fla. (AP) -- For the first time since 1999, Andre Agassi will head into the clay court season without a tournament title in the first three months of the year.
He turns 34 next month, and it has been nearly a year since he won a final. His bid for a fourth consecutive title at Key Biscayne ended Tuesday when he lost in the fourth round to journeyman Agustin Calleri at the Nasdaq-100 Open.
Agassi plans to keep plugging away, and the goal is to add to his total of eight Grand Slam championships. He has won the Key Biscayne title six times, but his 19-match winning streak in the tournament was ended by Calleri, 6-2, 7-6 (2).
"I missed some chances," Agassi said. "I needed to step it up and play to his standard, and I didn't do that."
With a career record of 799-244, Agassi was seeking a milestone victory. Instead, the 27-year-old Calleri earned a win he ranked with the best of his career.
Calleri served poorly but dominated from the baseline, repeatedly skipping shots off the line. The Argentine hit 47 winners, many on backhands into the corner that Agassi didn't even try to chase.
"Calleri was hitting his big shots, and it looked like Andre wasn't expecting that to happen, maybe," said Vince Spadea, who will play Calleri on Thursday.
The unseeded Spadea, denied a berth Monday on the U.S. Davis Cup team, added to his recent run of upsets by beating No. 9 Paradorn Srichaphan 5-7, 6-3, 6-2.
On the women's side, top-seeded Serena Williams won the tournament's most lopsided quarterfinal since 1996, beating Jill Craybas 6-0, 6-1. Williams' opponent in the semifinals Thursday will be No. 25-seeded Eleni Daniilidou, who beat Karolina Sprem 6-1, 6-3.
In other men's play, second-seeded Andy Roddick reached the quarterfinals for just the second time. He lost only 10 points on his serve and needed barely an hour to eliminate unseeded Guillermo Canas 6-3, 6-3.
Roddick's opponent Thursday will be No. 5-seeded Carlos Moya, who beat No. 19 Tommy Robredo 6-3, 6-3. Roddick is seeking his first semifinal berth in five tries at Key Biscayne.
Spanish 17-year-old Rafael Nadal was unable to summon the shotmaking that helped him upset top-ranked Roger Federer in the third round. Nadal lost to No. 21 Fernando Gonzalez 7-6 (1), 4-6, 6-2.