The 11-time world champion is not just surfing's most-decorated competitor, but at 52 one of world sport's greatest stories.

Despite nursing an injured hip that needed major surgery last September, the American remains one of the men to beat in the World Surf League.

That was proved again on Tuesday morning when Slater won his opening-round heat in the Rip Curl Pro at Bells Beach, beating Hawaiian star John John Florence.

Thirty years after he won the first of his four titles at Bells, Slater said on Tuesday this is most likely the last time he competes at the iconic event.

Australians Mick Fanning and Mark Richards are the only other men to win four Bells Beach titles.

"I haven't made an announcement, but I'm going to wrap this thing (his career) up pretty soon," Slater said after his heat win.

"So I'm just trying to enjoy each one that I'm at now."

Slater said he would reconsider retirement if he won a fifth Rip Curl Pro title - or the next event on the circuit, at Margaret River in Western Australia.

"It's probably my last Bells - not 100 per cent. I mean, if I win this one or Margarets, I earn my way back on tour next year," he said.

"But other than that, I'm fine if it's my last one, 30 years since I won my first, it would be a nice bookend.

"Bells isn't one of my favourite waves, but coming down here, it's one of my favourite events - just the experience.

"It will be a little bittersweet sadness when I'm not coming back for the event."

Slater missed the most recent world tour round in Portugal because of injury and Tuesday brought his first heat win of the season.

He is also expecting his second child, with Slater and his partner Kalani Miller making the announcement a few days ago.

His son Taylor, from a previous relationship, is 28.

"The important things in life change real quickly when you're having a kid, but I still got a little more stressed in that heat than I wanted," he said of Tuesday morning's win.

Slater's latest surgery on his long-term hip problem went for more than four hours and involved a body part from a cadaver.

"Who gave the ultimate sacrifice for me?," Slater said when asked for his reaction when he found out what the surgery would involve.

"I can surf, so I'm happy, but I'm not surfing (without) pain. Adrenalin helps."

As he contemplates a potential swansong at Bells Beach, Slater spoke of his mixed emotions about the venue.

"It's good to be back. It would be a real dream for me to hook in and to try to win here again, 30 years later," he said.

"But for now I'm just trying to enjoy the event, enjoy the people ... good vibes down here.

"If you look at my results, you can tell, it's love-hate.

"We've been fighting a lot, but sometimes we get along. It's a feel-good story if you win here, because it's such a challenging wave."

Surfing's most decorated star won his heat in four-to-six-feet conditions.

Florence joined Slater in progressing, with Hawaiian Seth Moniz finishing third in their to move into the elimination round.

The most recent of Slater's record 56 tour wins was at Hawaii in early 2022.

Australia's defending champion Ethan Ewing also won his opening-round heat, as did compatriot Jack Robinson.

Australian Associated Press