A building North Shore swell is building the drama for the final day of the O'Neill World Cup of Surfing.

The fourth round of the men's contest was run yesterday morning in 4- to 6-foot waves, but the action was halted at mid-day when wave conditions started to diminish.

The contest will wrap up today in what could be 10-foot waves or higher. The quarterfinals, semifinals and final have yet to be completed.

"We really need some big surf for the Triple Crown because, so far, it's been lackluster," said Randy Rarick, the executive director of the Vans Triple Crown of Surfing. "But if it works out (today), we could have an exciting final."

The O'Neill World Cup is the second of three events in the Triple Crown of Surfing.

After yesterday's heats, 16 surfers remain for the final day of this contest, including five from Hawai'i.

Kaua'i's Andy Irons continued his Triple Crown dominance by winning his fourth-round heat. Most of the surfers agreed with the call to halt the action, but Irons said he was willing to finish yesterday.

"I don't care either way," he said. "I'm ready to go. I (would) almost rather keep going. Right now, it's fine ... we surfed way worse (conditions) than this before."

Irons is the defending Triple Crown champion and the leader in the 2006 Triple Crown standings. He won the first event last month at Hale'iwa Ali'i Beach.

The other Hawai'i surfers advancing yesterday were Fred Patacchia Jr., Ian Walsh, Pancho Sullivan and Dustin Cuizon.

Cuizon advanced by catching a wave in the closing seconds of his heat.

"I knew I needed one more, so I feel lucky that I got that last wave to give me the score," he said. "It's pretty hard out there. The waves are here and there, so you're paddling all over the place trying to find the waves. I think it's better to start again (today). There should be more waves to catch."

The O'Neill World Cup is also the final contest on the 2006 World Qualifying Series. The top performers from the final 2006 WQS standings get called up to the elite World Championship Tour.

Cuizon probably needs to reach the final of this contest to have a shot at getting called up.

"All I can do is take it one heat at a time," he said. "There's other guys ahead of me (in the rankings), so hopefully I can do something in this contest to move up."

Current world champion Kelly Slater of Florida also advanced yesterday, and he was pleased with the call to postpone action at mid-day.

"When Sunset is this size and inconsistent like this, it's really frustrating," Slater said. "The conditions are so difficult and tricky. You can paddle one way for a wave you think is there, and then all of a sudden you turn around and the next guy is catching a wave where you were at before."

Despite yesterday's diminishing conditions, some surfers were able to post impressive scores. Australia's Joel Parkinson had a near-perfect wave of 9.8 (out of 10), and a two-wave total of 17.8. David Weare of South Africa had a two-wave total of 17.5.

Three Hawai'i surfers were eliminated yesterday: Jesse Merle-Jones, Jason Shibata and Kekoa Bacalso.

For updated status of the contest, call 596-7873 or visit www.triplecrownofsurfing.com.

QUARTERFINALS (TOP TWO FROM EACH HEAT ADVANCE)

Heat 1: Jay Thompson (Australia), Pancho Sullivan (Hawai'i), Joel Parkinson (Australia), Kelly Slater (Florida)

Heat 2: Dean Morrison (Australia), Fred Patacchia Jr. (Hawai'i), Odirlei Coutinho (Brazil), Ian Walsh (Hawai'i)

Heat 3: Darren O'Rafferty (Australia), Neco Padaratz (Brazil), Andy Irons (Hawai'i), Dustin Cuizon (Hawai'i)

Heat 4: David Weare (South Africa), Marcelo Trekinho (Brazil), Mick Fanning (Australia), Jordy Smith (South Africa)

Reach Dayton Morinaga at dmorinaga@honoluluadvertiser.com.