Rory McIlroy unusually changed drivers mid-tournament after admitting he wasn't enjoying watching Tiger Woods hit the ball past him at the Genesis Invitational.
Woods, 47, is making his long-awaited return on the PGA Tour in his first competitive start since the Open Championship at St Andrews in July.
And the 15-time major champion is set to make the cut at one-over as he continues his recovery, two years on from a horrific car crash that threatened his ability to walk.
McIlroy, meanwhile, is poised four shots behind leader Max Homa as he targets an immediate return to world number one in Los Angeles.
But the Northern Irishman was not content with his four-under 67 in round one as his close friend and playing partner Woods remarkably outdrove him on more than one occasion off the tee.
Woods is still impeded by several restricting injuries but somehow managed to blast the ball past big-hitting McIlroy on Thursday, reaching an incredible ball speed of around 180mph, which is nearly 10mph higher than tour average.
After the round, McIlroy promised a visit to the driving range as he took no pleasure from being outdriven on Riviera's bounding fairways by an ageing Woods.
“I’m going to go work on the range,” he said on Thursday evening. “I put my driver up a click in loft at the start of the week; I might have to turn it back down again. I don’t like [Tiger] hitting it by me.”
And McIlroy went one further than simply adjusting his driver loft as he added a different club to his bag for his second round on Friday morning.
Barstool Sports reporter Dan Rapaport noted that the 33-year-old used TaylorMade's Stealth 2 Plus driver at 9.0 degrees of loft, instead of the first-generation TaylorMade Stealth Plus in round two.
While McIlroy couldn't improve on his first round 67, his decision to change drivers seemed an inspired one as he crushed it off the tee during his two-under par 69.
The 33-year-old staggeringly hit a 388-yard drive, leaving him just short of the green on the par-4 third hole. But it was on the greens where McIlroy proved most frustrated as he had to wait until his final hole of the day to sink a birdie putt from any meaningful length.
He failed to birdie any of the three par-5s, but is still lurking in contention heading into the weekend on a strong leaderboard which also includes Jon Rahm and Collin Morikawa.
“I certainly drove the ball much better today,” McIlroy said. “I didn't play the par-5s as well today. That's the key to this golf course is birdieing the birdie-able holes. I didn't quite do that today. I made the birdies on the tougher ones, but hopefully going into the weekend, I'll sort of tidy all that up.”
