The top-seeded Isner beat 6-foot-8 South African Kevin Anderson 6-7 (3), 7-6 (2), 7-6 (2) on Sunday to win the Atlanta Open in the tallest final in ATP Tour history. Anderson was seeded second.
The pro-Isner crowd had to sweat during the longest tour final - 2 hours, 54 minutes - this season.
Nobody should have been surprised that it came down to tiebreakers.
''This is a tournament where I could have been out in my first match. I lived on the edge all week, and seemed to come through for the good every time,'' Isner said after winning two of three tiebreakers to push his ATP-best tiebreaker record to 26-7. ''It feels good to be on the right side.''
Isner played at least one tiebreaker in all four of Atlanta matches (seven total), and he played at least one tiebreaker in 11 of 13 matches prior to Atlanta, 17 overall.
When Anderson snapped Isner's streak of 12 straight tiebreaker wins to capture the first set, there was cause for concern. In all eight previous Isner-Anderson meetings, the winner of the first set won the match.
Anderson won the first set tiebreaker, 7-3, as Isner unleashed a couple errant forehands following his own serves.
Isner also found trouble early in the second set. Trailing 1-0, he faced a triple service break. After battling back to deuce twice, he served Ad-out only to unleash one of his 24 aces on the way to holding serve. Isner had 95 aces in four matches.
He faced 11 service breaks Sunday and won them all, often with aces. He missed on his only chance to break Anderson's serve.
''I had a couple chances,'' the South African said. ''He's proven himself to serve well when it matters. He stepped it up well. Even if I was the better player in the majority of the match, he stays in there.
''He definitely played two better tiebreakers than me; there's no question about that.''
Getting to that third tiebreaker was dicey for Isner.
Trailing 5-6, he faced two match points. The first time, Isner boomed a 143 mph ace. The second time - in a game that was at deuce five times - Anderson sent an unforced backhand error into the net.
The third tiebreaker was another 7-2 walkover.
Anderson served first and after his first found net, Isner correctly guessed at what was coming.
''On his second serve, he was never going out wide,'' Isner said. ''So I told myself I was going to go around it (to hit forehand), and if he hit an ace so be it.''
Isner returned, and Anderson sent a backhand into the net. Isner moved to 3-0 with a 141 mph ace and a 143 mph winner.
On his last serve, Isner lasered a 146 mph winner for a 6-1 lead. Anderson won the next point on serve, but the match ended when he went to the net following his serve and sent another backhand wide.
Anderson's service game was broken just once in 11 sets in Atlanta, but in the third tiebreaker Sunday, Isner won points on Anderson's first, third and fifth serves.
Isner lost in the 2010 and '11 Atlanta finals.
''It feels amazing because I lost to Mardy (Fish) twice, and losing to (eventual winner) Andy (Roddick) last year in the semis,'' said Isner, who survived a third set triple service break to force a tiebreaker before beating Lleytton Hewitt in the semis. ''I've been super close.''
Isner earned $98,700 and will move up from his world rank of 22 and likely pass Sam Querry (20) as the top American. Isner is 6-3 against Anderson, who began the tournament ranked No. 21. Anderson took home $52,000.
France's Edouard Roger-Vasselin and the Netherland's Igor Sijsling won the doubles title, beating Britain's Colin Fleming and Jonathan Marry 7-6, 6-3.
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