WINSTON-SALEM, N.C. (AP) - In the all American semifinal of the Winston-Salem Open, fourth-seeded John Isner upset top-seeded Andy Roddick 7-6 (7), 6-4 Friday in the Winston-Salem Open, a final tuneup before the U.S. Open.

Isner won the first set in a tiebreaker by breaking Roddick's serve to go up 8-7. He ended the set with a 107-mph serve.

"I was flat out just luckier than he was in the first set,'' Isner said about advancing to his third finial of the season.

The 28th-ranked Isner will play qualifier Julien Benneteau, who defeated 10th-seeded Robin Haase 3-6, 7-6 (7), 7-6 (6) in the other semifinal that took nearly three hours to complete. Isner and France's Benneteau will play in Sunday's final at 12:30 p.m.

Roddick and Isner held serve in the first set and it came down to Isner breaking Roddick's serve to go up 8-7. Isner, who has what many consider one of the best serves in the game, then ended the set with an ace. The 21st-ranked Roddick, who had been 8-0 in his career in Winston-Salem, broke Isner in the second set to go up 3-1. But Isner came right back to break Roddick in the next game.

``He played a pretty good game down 3-1 and he was a little tired but slapped a couple of balls in and all of sudden I'm in hole down love-30,'' said Roddick, who is ranked 21st in the ATP.

Tied at 4-4, Isner got another break to go up 5-4 and had three aces to end the match. Isner's ability to return Roddick's second serves was crucial. For the match Isner returned 70 percent of those second serves.

"I was just thinking in a match like that it's important to get up in the return game,'' Isner said. Roddick, who has been mostly idle this summer because of an adnominal strain, was glad to get in four matches in preparation for next week.

"Obviously I'm upset because I feel like I played the better first set,'' Roddick said. "And he definitely played better in the second set I haven't played tennis at all, but I'm really happy because I haven't played four matches in a week since March. I think this week served its purpose for me in preparation for the U.S. Open.''

Isner, who is 6-foot-9 and 240 pounds, was bothered by the heat and humidity early in the second set, but said he caught a break when the clouds rolled in.

``I think a big difference was the sun went behind the clouds,'' he said. "I'm serious, that really helped.''

Isner hasn't backed down from the challenge of performing well in front of family and friends. He grew up in nearby Greensboro before his All-America career at Georgia.

"It's nice,'' said Isner, who has stayed all week with his parents and driven over to the tournament each day.

"I was just looking forward to coming back home because it had been eight months since last Christmas since I had been in the state of North Carolina. I had a lot of time to rest and relax, and physically I felt pretty good even though this is my fourth event in a row.''

Benneteau, who had to win two matches last Saturday and another one on Sunday just to get into the tournament, is ranked 113th. Haase had match point three different times but couldn't put it away.

The challenge for Benneteau in Saturday's final will be dealing with the home crowd that will favor Isner. He will also have to cope with fatigue after playing eight matches in seven days.

"Benneteau has kind of been on the shelf, but he came through qualifying so he's had a lot of matches,'' Isner said, "but he's pretty confident.''

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