Jamie O'Brien shot through big barrels early and often on the first day of the Da Hui Backdoor Shootout contest yesterday.

As a result, O'Brien is now in the top position for the four-day event.

The opening day was run in waves of 10 to 15 feet at the Banzai Pipeline, with wave-faces reaching as high as 30 feet.

"It's not perfect Pipe, but it's a perfect day," O'Brien said. "I'm pretty content. I think I'm placing no matter what, but I don't know if it's going to be first or sixth."

The Shootout follows a unique format in that no surfers are eliminated. Each surfer will get to surf for an equal amount of time for all four days. The top three scores for each surfer from any of the four days will count.

O'Brien's top three waves yesterday received scores of 42 (out of 48), 38.4 and 37.4 for a total of 117.8.

"I don't remember what happened," he said of his best ride. "I just remember the ending. I just squeaked out."

Nathan Fletcher is currently a distant second with a three-wave total of 97.2.

In essence, the rest of the field has three days to match O'Brien's first-day performance.

"Jamie is going to be tough to beat," said Pancho Sullivan, who won the Backdoor Shootout in 2004. "But this is such an incredible wave, you can get three perfect scores in one heat."

O'Brien grew up — and still resides — in a house right in front of the famous Pipeline.

Other standouts yesterday included Bruce Irons, Mark Healey, Kalani Chapman and Ola Eleogram.

Reach Dayton Morinaga at dmorinaga@honoluluadvertiser.com.