The pair played five extra holes at the San Diego layout’s South Course to cap off a gruelling final day but with three birdies and two pars apiece, the pair couldn’t be separated.
They will return to the course at 8am local time (3am Eastern time in Australia) to continue the battle after what has already been a thrilling week of golf.
With the hype surrounding Tiger Woods’ comeback and a final day which saw the lead change hands several times, fans could hardly be more excited about what is to come in 2018.
American Ryan Palmer was also part of the playoff after making a brilliant final hole birdie to match Noren and Day at 10-under but a par at the first extra hole saw him eliminated.
After making his third birdie of the playoff in near darkness at the par-5 18th Day said he had no issue with returning to decide the title.
“I’m just going to try to get some rest tonight and I’ll play all day tomorrow if I need to to get the win,” he told CBS’ Peter Kostis.
"I can't see it."January 29, 2018
“But this is why we practise. It’s a lot of fun to be out here in amongst the crowds. I mean, Alex is playing some tremendous golf…to be able to go through and go shot for shot there was pretty special.”
Day’s final round of 2-under 70 lifted him from a share of fifth place to sudden death on a day where only two players shot in the 60’s.
Noren was among those who struggled, a 1-over 73 with no back nine birdies a somewhat disappointing round.
Coming to the par-5 last needing a birdie to win he would have liked his chances but had to endure a nearly five-minute delay while playing partner JB Holmes agonised over his second shot.
After Holmes eventually decided to lay up, Noren blasted his second well over the green and had to take relief in an awkward spot next to the green.
The incident attracted plenty of attention on social media with Holmes roundly criticised for the delay though to his credit Noren never indicated it had bothered him.
The World Number 19 did well to make par to force extra holes and was stellar in his play in extra time.
While Day declared he would have happily played on with some cars to light up the fairway, Noren seemed pleased to stop.
“It’s too dark,” he told Dottie Pepper. “I could barely see that last putt.”
“If we had some more sunshine it would be nice to get it finished but its better this way than maybe missing a short one when you can’t see.”
Marc Leishman was next best of the Australians continuing a good run of form both in 2018 and at Torrey Pines where he has twice been runner-up.
Despite a final round 73 he moved up four places on the leaderboard to be T8, two shots ahead of Australian PGA Champion Cameron Smith.
Scores of 71-68-73-72 saw Smith to a T20 result, the last of the Australians to finish under par.
Cameron Davis endured a horror final round of 80 to tumble 33 places down the standnings for an eventual T58 finish.
Rod Pampling, Aaron Baddeley, Matt Jones and Geoff Ogilvy all missed the cut.
Tiger Woods fired a final round of even par 72 and at 3-under for the week finished T23.
PROS WEIGH IN ON WHAT MAKES A BAD COURSE:
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