Rory McIlroy earned a share of the first-round lead after the former world number one carded a six-under-par 66 at the Hero World Challenge.

McIlroy – winner of October's CJ Cup – was almost flawless on the opening day as the four-time major champion joined Daniel Berger and Abraham Ancer a stroke clear atop the leaderboard.

McIlroy had an eagle, six birdies and a double-bogey at Albany Golf Course in the Bahamas on Thursday.

"It was nice to play the back nine the way I did and put myself back in the tournament," said McIlroy, who did not drop a shot on the back nine with three birdies and an eagle, which he improbably chipped in.

Berger boasted a four-shot advantage at one point in the first round after bursting out the blocks with four consecutive birdies, though two bogeys on the back nine undid some of that good work.

But McIlroy and Ancer ensured the American must share the lead entering Friday's second round, the former going five-under following the turn at the PGA Tour tournament.

Similar spot.
Same result.@McIlroyRory gets it to 5 under. He's 1 back. https://t.co/tBMqTKTupj pic.twitter.com/epHsTX0Hz9
— PGA TOUR (@PGATOUR) December 2, 2021

Fellow leader Ancer finished in similar style, despite also faltering with a bogey on the ninth, recording five birdies after the halfway point to join the group on six under.

It looked like there would be a different leader, however, with American star Justin Thomas a shot in front until the final hole, which he double-bogeyed.

Brooks Koepka – a four-time major champion – joins the 2017 PGA Championship winner after registering 67, with Webb Simpson also a shot off the initial mark.

The quality on display does not stop there, with Tony Finau, Patrick Reed, Viktor Hovland and Collin Morikawa all managing 68 to sit two shots off the three-man leading pack ahead of day two.