Rory McIlroy wasted little time in his search for a "spark" to ignite his season as he enjoyed a superb start to the BMW PGA Championship.
McIlroy, by his own admission, has an "up-and-down" record in the event having missed the cut four times in eight appearances, although he won his first professional title in the UK at Wentworth in 2014.
That victory prompted a sensational run of form as he won both The Open and PGA Championship either side of the WGC-Bridgestone Invitational, and he will be looking to emulate that after firing a confident five-under 67 in the opening round.
The 29-year-old, making his first appearance at European Tour HQ since 2015, struggled initially as he followed two pars with a bogey at the third, but he steadied himself with a birdie at the long fourth before converting excellent approaches to the sixth and eighth.
McIlroy dropped his second shot of the day at nine, but he bounced straight back with a nice two at the 10th and his all-round game looked in fine order throughout the back nine as he picked up further shots at 12, 14 and 16.
He lipped out from 12 feet for another at the 17th, and he carved his second way right following a perfect tee shot at the last, although he caught a break with a fortunate ricochet off the branches and back onto the short grass.
McIlroy then almost holed his pitch for eagle, his ball rattling the pin and staying out, but he did end the day on a sour note when he missed from inside three feet and had to settle for a par which left him two shots behind outright leader Lucas Bjerregaard.
"I think I did everything pretty well," McIlroy said. "I drove the ball much better and put the ball in play off the tee a lot more than I've done the last couple of weeks, so that's really good. I gave myself a lot of chances and I took most of them. I'm a little frustrated I couldn't get a birdie or two out of the last couple of holes, but overall, a really good start."
McIlroy is among the early starters in Friday's second round, and he will resume his challenge two shots behind Bjerregaard after the Dane stole the outright lead from South African pair Dean Burmester and Darren Fichardt.
Bjerregaard and Fichardt were the only two players in the field to keep a bogey off their cards on day one, with Bjerregaard tapping in for his seventh birdie at the last after coming perilously close to finding the water hazard with his second before shaving the edge of the hole with his chip from the fringe.
Veteran Fichardt enjoyed a run of four birdies in six holes around the turn before another at the 17th lifted him alongside his compatriot Burmester, who put together a sensational final third of his 66.
Burmester was level par after 11 holes, but he made back-to-back birdies at 12 and 13 before holing his second to the tough 15th for a rare eagle-two on what is traditionally the toughest hole on the West Course.
He also birdied 16 and 17 to be first into the clubhouse on six under, finishing the day one ahead of McIlroy and English pair Richard Bland and Matt Fitzpatrick.
Bland closed out his 67 with three birdies over the last four holes, while Fitzpatrick did his damage at the start of his round as he birdied the first, third and fourth despite the wet and cool conditions early in the day.
Alex Noren began the defence of his title with a solid 69 despite taking six to negotiate the 17th, while Shane Lowry was left to rue an expensive finish when the Irishman was challenging for the lead with one to play.
Lowry's first drive at the 18th disappeared into the shrubbery and was not found, and he compounded the error by knocking his fourth shot into the water before doing well to get up and down for a double-bogey seven.
European No 1 Tommy Fleetwood was happy with a "patient" 70, the same score handed in by newly-appointed Ryder Cup assistant captain Lee Westwood, while Paul Casey battled to an erratic 72 in his first outing since pulling out of The Players Championship with a back problem.