Playing in the same group, Triplett and Austin each shot 3-under 68 to finish at 10-under 203 at Newport Beach Country Club.
Jeff Maggert and Scott McCarron finished a stroke out of the playoff. McCarron three-putted the 18th from 30 feet for par and a 68. Maggert shot 65, but couldn't overcome a four-putt triple bogey on 18 in the first round Friday.
Fran Quinn, three strokes ahead entering the round, had a 74 to tie for fifth with Paul Goydos (68) and Steve Flesch (69).
Newport Beach resident Fred Couples closed with a 69 to tie for 10th at 6 under.
Vijay Singh skipped his title defense to play in the PGA Tour's Arnold Palmer Invitational. Bernhard Langer is sidelined by an injury to his rib and stomach area.