John Isner fired 16 aces in a 7-6 (7/1), 6-4 victory over Australian Lleyton Hewitt on Sunday to win the ATP Hall of Fame Championships title for the second-straight year.
"It's huge for me," the top-seeded American said. "It's the first time I've ever defended a title. I'm very happy to come through today against a great opponent -- in my opinion one of the greatest ever. It's a big win for me."
Hewitt, who received a wild card into the draw, was playing in his first final since June 2010, when he captured his 28th career title on the grass courts at Halle.
The two-time Grand Slam champion and former world number one from Australia has battled a string of injuries in recent years and underwent radical foot surgery in February.
Isner's triumph ended Hewitt's unbeaten career run in grass court finals, putting his record at 7-1.
But with his run to the championship match, Hewitt is projected to rise from his current 233rd in the world to about 151 in the world rankings.
His performance was also a morale-builder as he prepares for the Olympic tennis competition at Wimbledon, where the 31-year-old Aussie will play singles as a wild card entrant.
Isner is also slated for Olympic action and welcomed the chance to tune-up for the Games with tournament competition.
He'll fit in one more ATP tournament before the Games, heading the field at the Atlanta tournament that starts on Monday.
"The best practice is match practice," said Isner, who saved the only break point he faced in the match in the first set.
The American gained the only break of the contest to take a 2-1 lead in the second set, and that was the only opening he needed.
After Hewitt saved one match point against his serve in the ninth game, Isner closed it out with a dominant service game that opened with two aces, followed by a service winner and his final ace of the match on his second match point.
Isner claimed his fourth career title, and his first of 2012 after runner-up finishes at Indian Wells and Houston.