NEWPORT, R.I. — Two-time defending champion John Isner won the battle of the tallest players on the ATP tour, defeating Ivo Karlovic of Croatia, 7-6 (7-3), 7-6 (7-3), on Friday to advance to the semifinals of the Hall of Fame Championships.
In the other quarterfinal match, No. 4 seed Lleyton Hewitt of Australia beat qualifier Jan Hernych of the Czech Republic, 6-7 (3-7), 6-4, 6-2, setting up a rematch up of last year’s final when Isner captured the title in straight sets.
On Friday, Isner won his 13th straight match on Newport’s grass courts and raised his mark to 13-0 in tiebreakers during the streak.
The second-seeded Isner, who stands 6 feet 9 inches, served 23 aces, including three in each of the tiebreaks. Karlovic, who is 6-10, had 14 aces, but double faulted on the match’s final point.
Both players served over 70 percent in the match, most ranging between 120-130 miles per hour. Neither broke in a game.
‘‘He served at a pretty high percentage,’’ said Isner, ranked 19th in the world, the highest American coming into the week. ‘‘Any time guys like us serve in the 70s, it’s going to be tough for anyone to break us.’’
Karlovic played his first ATP tournament since being sidelined with spinal meningitis from late April to early May. He called for a trainer early in the opening set.
‘‘I was dizzy a little bit and it was difficult to focus,’’ the 34-year-old said. ‘‘I was a little worried that it was the virus or something. It wasn’t. I was tired. I wasn’t used to playing that many matches.’’
Karlovic was satisfied with how he played in the tournament.
‘‘I was just happy I was here,’’ he said. ‘‘If anyone told me I’d be in the quarters, I would say he’s nuts.’’