Despite continuing to struggle off the tee, McIlroy carded a second round one-under-par 69 for a halfway total of level par to lie just five off the lead shared by Scottie Scheffler, Corey Conners and Viktor Hovland.

First-round leader Bryson DeChambeau and fellow American Justin Suh were two shots off the lead, with England's Callum Tarren – who only secured a place in the field on Friday after former champion Martin Kaymer withdrew – another stroke back after a superb 67.

Masters runner-up Brooks Koepka was alongside Tarren on two-under thanks to a 66 that included four birdies in the last seven holes.

Justin Rose hit just two fairways but somehow conjured up a 70 to lie one-under, with McIlroy and former Open champion Shane Lowry on even par.

"When I holed that (birdie) putt on the last I thought I can't believe I'm only five back." - Rory McIlroy.

McIlroy was among the later starters who took advantage of unexpectedly calm conditions and a course softened by several rain showers to cover his last 10 holes in three-under.

"I need to be patient the way I'm hitting it off the tee," McIlroy said. "I stayed really patient and I think it was rewarded with a couple of breaks and birdies towards the end.

"I think with how terribly I've felt over the ball, the fact I am only five back. I'm not saying it could be up there with one of my best performances but when I holed that (birdie) putt on the last I thought I can't believe I'm only five back.

"If I can get the ball in play off the tee I'll have a shot and at this point I might just tee it high and bomb it everywhere. I may as well just swing it hard and go for it."