US hopes of winning the first-ever men's Olympic surfing competition ended on Tuesday when Japan's Kanoa Igarashi eliminated Kolohe Andino in the quarter-finals.
Andino had knocked out team-mate John John Florence in the previous round, but Igarashi was too hot to handle with a tropical storm whipping up wild waves at Tsurigasaki Beach.
"Unfortunately I couldn't carry the momentum forward, but I tried my best and that's all I can do," said Andino, who had ankle surgery just weeks before the Games.
Organisers moved the medal events of surfing's Olympic debut forward to capitalise on favourable wave conditions.
That quarter-finals, semi-finals and finals of the men's and women's events will all be contested on Tuesday.
Igarashi, whose father grew up surfing on the same beach, was the first to advance to the men's semi-finals.
"Today was one of those days where it's man against ocean, more so than competing against your competitor" he said.
"It just makes it fun. We've had every condition at this event so far, we've had to dig deep and today's no different."
Brazil's Gabriel Medina and Italo Ferreira -- two of the favourites for the gold -- were in action later in the morning.
Americans Carissa Moore and Caroline Marks are both still involved in the women's competition.
Australia's seven-time world champion Stephanie Gilmore and French world number two Johanne Defay were eliminated on Monday.
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