The ATP began keeping records on aces in 1991. Karlovic shared the previous record of 51 aces with Joachim Johansson. The old mark for aces in a French Open match was 37, set by Andy Roddick in 2001.
Karlovic, the tallest man on the ATP tour at 6-foot-10, fell to 0-11 in five-set matches, which also is a record.
“To play him on any surface, he’s so dangerous,” Hewitt said. “(He served) a lot of unreturnables.”
Karlovic had 15 aces in the first set, 12 in the second and 14 in the third. All three of those sets went to tiebreakers, and Karlovic was broken only once in those three sets. In the final two sets, Karlovic had seven aces in each.
“I didn’t feel I was 100 percent after the second set,” said Karlovic, who said he lacked energy under the Paris sun.
Hewitt, a two-time Grand Slam champion, finished with 19 aces.
At Wimbledon in 2003, Hewitt lost to Karlovic to become the first man in the Open era to lose in the first round as defending champion at the All England Club.
If Hewitt beats Andrey Golubev of Kazakhstan in the second round, he could end up facing four-time defending champion Rafael Nadal in the third.
“Today was a big enough hurdle,” said Hewitt, who had hip surgery last year.
Marat Safin, another of the eight former Grand Slam singles champions in the men’s field, also advanced. The Russian beat Alexandre Sidorenko of France 6-4, 6-4, 6-4.
“Every round is a tough one,” said Safin, who is planning to retire at the end of the season. “I’m trying but I’m really suffering on the court right now. But I’ll try to play better next match and I hope that I will get through.”
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No. 13 Marin Cilic of Croatia defeated Jan Hernych of the Czech Republic 6-0, 6-4, 6-3.
Also in the men’s field, third-seeded Andy Murray was scheduled to play Juan Ignacio Chela later Sunday.
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