Performing at the Billabong Pipe Masters in Hawaii, the 46-year-old was up against Brazilian Filipe Toledo in the third round, when he found himself in trouble - but miraculously pulled himself out.
Dubbed the 'the Houdini tube ride', the American got knocked off his feet by a wave, fell off his board, but somehow pulled it back underneath, bodyboarded briefly, before jumping back to his feet and exiting with arms raised in celebration.
The 11-time world champion tweeted later: "Well, that was interesting.
"I thought I just fell straight onto my belly and bodyboarded out. Didn't realise I had to grab for it!
"Haha, fun day."
Slater, who has announced he will retire after the 2019 world tour, dispatched Toledo and has since progressed through to the semi-finals.
Photo source Twitter