Youth edged out experience in the all-Australian clash at Supertubos as Molly Picklum beat Tyler Wright to reach the semi-finals at Rip Curl Pro Portugal.
With World Surf League leader Caitlin Simmers knocked out at the last-eight stage Picklum can move into the lead if she wins at Peniche for the first time.
Strong waves then called off conditions early into the men's last-32 heats on Monday, but not before Jack Robinson had ridden a pair of barrels to score big and make the quarters.