Sebastian Munoz sank two eagles in an eight-under-par 64 that gave him a one-shot lead at the Zozo Championship while Rory McIlroy let his frustrations get the better of him following a patchy first round.
World number three Justin Thomas got hot on the back nine, finishing eagle-birdie-birdie for a seven-under 65 to climb into a tie for second with England's Tyrrell Hatton.
The tournament is being played at the Sherwood Country Club in Thousand Oaks, California instead of Japan due to logistical issues caused by the Covid-19 pandemic.
Munoz, coming off a top 10 finish at last week's CJ Cup, had a shaky start after his tee shot on the first hole found the rough and led to the first of his two front-nine bogeys.
But the Colombian then landed four birdies over the next five holes before drilling in his first eagle at the seventh, making the turn at four under.
His rollercoaster round continued on the back nine where he added four more birdies, a double bogey and an eagle after holing out from over 50 yards on 16.
McIlroy was three-under after his front nine but three bogeys and two double bogeys thereafter left him with a lot of work to do to force his way into the reckoning for the weekend.
A rollercoaster back nine started with back-to-back bogeys, a tee shot into the water on the 15th and then a closing double bogey, during which he pressed his club into the turf so hard that it snapped.
Meanwhile defending champion Woods struggled with all parts of his game in a four-over 76, leaving him tied for second to last.
A rare bright spot came when he drained an 87-foot putt on the 14th that elicited a broad smile from the American.
Despite world number one Dustin Johnson and Australian Adam Scott being sidelined due to positive Covid-19 tests, the event still boasts a strong lineup including world number two Jon Rahm (68), Justin Rose (67) and PGA Championship winner Collin Morikawa (71).
The field has no cut and will be the last event for many of the players before the rescheduled Masters from 12 to 15 November.
