Antoine Rozner hit a flawless seven-under-par 65 to overtake Rory mcilroy and TyrrHatton to top the leaderboard after the second round of the World Tour Championship in Dubai on Friday.
Northern Ireland's McIlroy, bidding to equal Seve Ballesteros' mark of six European Tour Order of Merit crowns, and England's Hatton had led overnight in the season-ending tournament.
Frenchman Rozner finished with four straight birdies and had no bogeys as he took a one-shot lead over McIlroy and Hatton, who both hit 69.
"It's one of those days where everything goes in and I had a ton of fun out there," said world number 154 Rozner, who carded 70 in the first round.
"I just think the confidence clicked and everything is going the right way."
McIlroy only needs a top-10 finish to secure a sixth Race to Dubai title of his career, matching Ballesteros.
McIlroy made a fast start with three birdies in his first four holes.
Another followed at the seventh as he climbed to nine-under, only to bogey the eighth and 10th to gift the lead to Rozner.
McIlroy parred his way to the par-five last, where he produced a stellar second shot inside 15 feet and brushed the left edge of the cup with the eagle putt which would have seen him rejoin the lead.
"A little disappointed that I didn't kick on after such a great start, four under through seven," McIlroy said.
"At this point, I'm just trying to win the golf tournament and if I win the golf tournament then everything else that happens alongside that is nice.
"Right now, my focus is, you know, I'd love to get my third title here at the Earth course, and if I can do that, then yeah, everything else will be great.
"It was nice to finish with a birdie and at least shoot something in the 60s after the start that I had."
McIlroy is searching for his first title since May after a frustrating year punctuated by several near-misses, including in agonising fashion at the US Open.
Hatton had to grind his way into contention after bogeying the fourth, hitting back with a birdie putt at the sixth before adding another at the eighth.
The world number 18 holed from eight feet at the 10th to pick up a shot and when he holed a clutch putt from eight feet for birdie at the 15th, he was one adrift of Rozner.
Chile's Joaquin Niemann carded an eagle, five birdies and two bogeys in his 67 to sit at seven-under in sole fourth.
How it stands at the halfway mark at the season finale in Dubai 📊#DPWTC | #RolexSeries pic.twitter.com/c6YXFX0Qsd
— DP World Tour (@DPWorldTour) November 15, 2024