Patrick Reed is on course to win the DP World Tour Championship and the Race to Dubai after a sublime second round gave him a two-shot lead.
Reed started the season-ending tournament in Dubai in pole position to become the first American to be crowned European number one.
Victor Perez led after the opening round to take the initiative in the Race to Dubai battle, but Reed took charge at Jumeirah Golf Estates on Friday with a stunning eight-under 64 to lead by two shots at the halfway mark.
Reed made five birdies on the front nine to go out in 31 and the only blemish in what was the lowest round of the week came when he bogeyed the 12th.
The world number 11 put that setback behind him by making three gains in the last four holes to reach 10 under and a two-shot advantage over Matt Fitzpatrick.
"Anytime you shoot eight under par you're always happy," said Reed, who avoided a second dropped shot of the tournament with a great up and down at 13 following a poor tee shot.
"I feel like today I got off to a little better start than I did yesterday and the putter was working a little bit.
"There's a lot of golf left. I feel like the biggest thing is yesterday just seemed like I kept burning edges, and a couple iron shots and scoring clubs that I didn't hit as close as I needed to and wanted to.
"I was able to warm up a little bit last night on the range after the round and tighten things up, and today I gave myself a lot of chances. I hit it close on a lot of holes and therefore I saw lines a little better and I was able to free up the putter and make some putts."
There were seven birdies for Fitzpatrick in his second successive four-under 68, while fellow Englishmen Tyrrell Hatton (68) and Laurie Canter (66) trail Reed by three shots.
Perez dropped back to three under with a 74, having dropped four shots in as many holes just after the turn.