Brazil's Italo Ferreira and American Carissa Moore led the way by winning the first two heats as surfing made an emotional Olympic debut on a sweltering Sunday at the Tokyo Games.
Saturday's lame waves for the final training session were quickly forgotten as the morning swell offered the power the surfers were looking for to showcase their sport during the 30-minute heats.
"I'm so stoked, it's a special event and I've been training a lot these last couple of months, I'm so glad to be here," Ferreira told reporters after edging out Hiroto Ohhara, Leonardo Fioravanti and Leandro Usuna in the day's first heat.
In the women's competition, world number one Moore scored a narrow win over Teresa Bonvalot of Portugal.
"Yesterday, I actually had a little mini-meltdown because of all the nerves and the anxiety and stuff that had built up," Moore told reporters.
"I had more of a sense of calm going into today ... Whatever happens, I've done everything I could."
With the men leading off early, there was some discussion as to whether it was Ferreira or Argentina's Usuna who had caught surfing's first Olympic wave, but as the action continued, the Brazilian world number one showed his class.
"That was a terrible (first) wave," Ferreira laughed. "I did two turns and on the last one I fell, (but) I tried to catch a lot of waves and put scores on the board."
John John Florence continued his remarkable recovery from torn knee ligaments that required surgery in May, the American topping his heat with a storming performance in round two to make it into Monday's third round.
"It feels good, no pain or anything, and I think every day that I surf it just gets better and better. I'm really stoked to make a couple of airs," he told reporters.
Australia's Stephanie Gilmore landed the best score of the day with a 14.50 mark in the first round.
For International Surfing Association president Fernando Aguerre, the day was the culmination of decades of work.
"My heart was beating faster than ever ... it was just emotion. This is a special moment, a special moment for me and for everybody that surfs, and for the Olympic movement," he told Reuters.
The competition continues as the 32 remaining surfers, 16 men and 16 women, go head-to-head in round three, with the women first out early on Monday morning.
(Reporting by Philip O'Connor; Editing by Stephen Coates, Karishma Singh and Ed Osmond)
