SAN JOSE -- John Isner makes no bones about his out pitch on the tennis court. He brings the heat, and with a first serve that registers in the high 130-mph range, he's basically dares his opponents to try to hit it.
Even when they do make contact on Isner's lasers, it's rarely for a decent return. He recorded only 10 aces in his 7-6 (8), 6-2 victory over Belgium's Xavier Malisse in the SAP Open quarterfinals Friday at HP Pavilion, but when he got the first serve in -- and he did two-thirds of the time -- it was almost an automatic point.
Isner won 37 of his 41 successful first serves -- a gaudy 90 percent -- and hit some of his best bombs when it mattered most during a first-set tiebreaker in which he fell behind 3-0 and had to overcome two set points to pull out a 10-8 squeaker against Malisse, the tournament's eighth seed.
"Just go out and throw a fastball," said the second-seeded Isner of his strategy. "I'm not going to try to kick a serve. I'm going to go for it and try to end the point off my serve. I did that in this match, and I've done it a lot in my career."
Isner could be on a collision course with another power server, top seed and two-time defending champion Milos Raonic of Canada, in Sunday's final. Raonic, now 10-0 in the SAP event over three years without having lost a set, beat Uzbekistan's Denis Istomin 7-6 (0), 6-3 in a similar match to start the evening session.
The SAP event, which will move to Brazil in 2014, could be going out in a blaze of glory this weekend, with the top four seeds having reached the semifinals for the first time since 2002.
In the opening quarterfinal, fourth seed Tommy Haas of Germany rolled past unseeded American wild card Steve Johnson 6-4, 6-2, and third-seeded Sam Querrey outlasted unseeded Colombian Alejandro Falla 6-3, 4-6, 7-5 in the late match.
The quarterfinal matches drew a total crowd of 10,057 -- 4,783 for the day matches and 5,274 for the evening session.
Isner faces a tough challenge in Saturday's semis against the well-rounded game of Haas. Because he is 6-foot-9 and not so fleet afoot, Isner understands that he isn't going to win a lot of long rallies. And because he relies so heavily on his serve, he doesn't break his opponent all that often, either. Hence, he winds up in a lot of tiebreakers.
He plays so many of them, though, he feels he has a distinct advantage once it goes to sudden death for a set.
"I am very confident (in tiebreakers)," he said. "I certainly have played a lot of them in my career, probably more so than your average tour player. It's something I feel comfortable doing. I try to stay even keel and just take care of my two points on serve. It puts a ton of pressure on my opponent."
Malisse had opportunities to steal the first set and possibly record the tournament's first major upset. But after jumping to a 5-3 lead in the tiebreak, he couldn't finish. Isner drilled a first serve to get back within one and finally broke back on Malisse's serve with a hard, deep return to knot it at 5-5.
From there, Isner didn't lose another point on his serve. He got three first serves in, and Malisse got none of them back over the net. Isner then won a point on his second serve to go up 9-8, and finally won the set when Malisse mis-hit an overhead backhand into the net.
As he did on Wednesday, Isner got stronger as the match progressed and broke Malisse twice in cruising through the second set. He said he'd have to be even better to beat Haas.
"That guy is such a good tennis player," said Isner of Haas. "He's an incredibly tough out. I'm going to have to serve very well and play my best if I want to win. If I don't, I don't think I can win."
The highest-ranking American in the world at No. 16, Isner is brutally honest that his success is all about his serve.
"I'm just not built to beat any of these guys from the baseline," he said "But if I serve well, I can be in the match against anyone in the world."
Raonic, who is looking to become the Bay Area tournament's first three-peat winner since Tony Trabert from 1953-55, could say the same. He opened his match against sixth seed Istomin with a 144-mph serve but played erratically through the first set. He found himself in the tiebreaker, however, reeling off seven straight points including an ace to finish it off.
Raonic, who will face Querrey in the semis, then won the first three games of the second set and rolled into the semifinals.
12:15 p.m.: Tommy Haas vs. John Isner. Approx. 4 p.m.: Milos Raonic vs. Sam Querrey. tv: csnCa, (1 and 8:30 p.m.)