GWANGJU, South Korea — American Caeleb Dressel almost set a world record in the 100 freestyle at the world championships on Thursday, and said he could not have done it without being pushed to the very end by his Australian rival Kyle Chalmers.

Dressel successfully defended his title, holding off Chalmers by .12 seconds for his third gold medal of the championships, but he said afterwards that he considered the Australian a better swimmer over 100 meters.

Dressel used a faster reaction time off the blocks and his renowned early speed to open a substantial half-second advantage at the turn, but barely held off a fast-finishing Chalmers over the final 50 meters.

Dressel's time of 46.96 seconds was an American record, only a whisker off the 46.91 world record held by Brazil's Cesar Cielo, who set the mark in a now-banned all-polyurethane suit in 2009.

"I respect the crap out of him and what he's done," Dressel said of reigning Olympic champion Chalmers in a poolside interview with American broadcaster NBC.

"I consider him a better 100 freestyler, so I look up to him in that aspect. I barely edged him. He's a heck of a racer. I could not have done that without him right next to me."

Chalmers, who was gaining on Dressel with every stroke late in the race, clocked a personal best 47.08, significantly faster than his gold medal-winning time at the 2016 Rio Olympics.

Dressel downplayed any suggestion that the pair had a cat-and-mouse rivalry, instead saying they both swam to their strengths. "We just have different strategies," said the 22-year-old from Florida.

"I think I've got more speed on him in that aspect of that sprint twitch. He goes up to the 200. I don't really do that."

With the rivalry set to continue at next year's Tokyo Olympics, Dressel knows he cannot rest on his laurels.

"I know I have to keep working because he's going to be better no matter what time I go, and I know that," said Dressel, who in 2017 matched Michael Phelps' record of seven world titles at a single championship. — Reuters