SAN FRANCISCO (CBS/AP) — A professional surfer competing in a contest Tuesday in the cold waters of San Francisco’s Ocean Beach left the waves before the end of his heat after saying he saw a large shark.

Surfer Dusty Payne, 22, of Hawaii left the surf while competing against Jordy Smith of South Africa. Payne said he spotted a large shark fin just outside the “lineup,” where surfers sit in the water and wait for their turn.

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“I was just sitting there, and I was waiting for a wave. I’ve seen dolphins before, and it wasn’t a dolphin,” Payne said during an interview on the beach with the Rip Curl Pro Search event’s camera crew. “It was the biggest fin I’ve ever seen in my life coming straight at me.”

A contest boat floating just offshore called in after the alleged sighting, saying they saw a dolphin, not a shark, said Dave Prodan, media director for the Association of Surfing Professionals.

“This obviously doesn’t preclude the situation of having both a dolphin and shark in the water at the same time, and event organizers launched a jet ski to further assess the situation,” Prodan said.

“Aside from Payne’s initial report, no further sighting of the animal was confirmed and the competition resumed without pausing.”

KCBS’ Margie Shafer Reports:

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The sighting follows an attack by a 9-foot shark on a surfer Saturday at Marina State Beach in Monterey County.

Eric Tarantino suffered injuries to his neck and arm, but was released from the hospital Monday.

While the waters off San Francisco are known to be host to white sharks, attacks are rare. The last attack, which was not fatal, occurred Nov. 2, 2005, according to the Shark Research Committee.

Despite Tuesday’s alleged sighting, the contest continued all day.

Ten-time world champion Kelly Slater, 39, won his heat, needing only one more winning heat during the San Francisco contest to capture his 11th title.

The contest in San Francisco began Tuesday, and is the first professional surfing event in the city in decades.

It is scheduled to begin again at 8 a.m. Wednesday.

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