McIlroy, who secured a one-shot victory in last year's contest to win the tournament for a third time, carded a three-under 67 in his first start since last month's runner-up finish in The Masters.

The former world No 1 mixed seven birdies with two bogeys and a double-bogey during an eventful opening round, keeping him in touch with a four-way tie for the lead that includes English duo Aaron Rai and Callum Tarren.

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"I think first week back after three weeks off, there's maybe going to be a couple of mistakes in there," McIlroy said. "The three-putt on 17 was an unforced error. I mean, 11 is a tough hole, I got a bit of a flyer from the semi rough and made bogey, but you sort of accept that and deal with that.

"I should have made five on No 6 when I hit it in the water but got a drop up there, so I probably left a couple out there. The three-putt there, if I hadn't made five. I'm still pretty happy with 67. It could have been a 65 or a 64, but it's still a good start."

Beginning on the back nine, McIlroy rolled in from 20 feet at the par-five tenth but failed to get up and down from a greenside bunker to save par at the next, before holing from 25 feet at the 12th to mark the start of four consecutive birdies.

McIlroy was unable to convert an eight-foot birdie look at the 16th and missed from a similar distance at the par-three next to card a three-putt bogey at the next, with the four-time major champion then racking up a double-bogey at the par-four fourth after finding water off the tee.

The defending champion responded by making a 20-foot birdie at the fifth and picking up another shot at the next, with two-putt pars over his closing two holes leaving him in the group on three under.

Wolff set the initial clubhouse target after four birdies in a five-hole stretch on his back nine helped him to a five-under 65, while McCarthy birdied four of his opening six holes and Rai made a bogey-free start to also move into the share of the lead.

"It's a very good start overall," Rai said. "Played very nicely, drove it well, hit some very good iron shots, made a good couple of up-and-downs at pretty important moments during the round. Everything moved along quite nicely, game felt solid and yeah, enjoyed playing the course. It's a great test this week."

Tarren recovered from an opening-hole bogey to hole a 25-footer on his final hole to add to the list on five under, with KH Lee and Nick Watney both posting four-under 66s.

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