RORY McIlroy turned back the clock to the days when he screeched off the Major championship starting line like a Ferrari when he fired seven birdies in a five-under 65 to hit the front in the US PGA at Southern Hills.

The Holywood star put on an exhibition of powerful driving, sensational iron play and deadly putting to send the field a message and leave playing partners Jordan Spieth and Tiger Woods seven and nine strokes adrift, respectively.

While he spoke in the build-up of playing conservatively and avoiding mistakes, he was on the front foot from the start in warm, blustery morning conditions, hit 12 of his 14 tee shots well over 300 yards and holing 108-feet of putts.

A disturbing 30 over par for the 27 majors he's played since winning his fourth grand slam title in 2014, his 65 was his lowest opening round in a major since he shot 65 en route to a record-setting eight-shot U.S. Open win at Congressional 11 years ago.

It’s also the first time he’s lead after the first round of a major since The Open at Hoylake in 2014, when he won.

In fact, every time McIlroy has shot 66 or better in the opening round of a major since becoming a major winner, he’s won.

"Yeah, look, it was a great start to the tournament," McIlroy said after recovering from bogeys at the par-three sixth and eighth holes by making a 19 footer for a closing birdie and a one-shot lead over Will Zalatoris and Tom Hoge.

"I've been playing well coming in here. I've been carrying some good form. Obviously, that took a lot from that last round at Augusta, played well up in D.C. at the Wells Fargo there, and played good in the practice rounds earlier this week.

"I think when your game is feeling like that, it's just a matter of going out there and really sticking to your game plan, executing as well as you possibly can, and just sort of staying in your own little world. I did that really well today. It was nice to get off to that good start and sorta keep it going.

"I feel like this course, it lets you be pretty aggressive off the tee if you want to be, so I hit quite a lot of drivers out there and took advantage of my length and finished that off with some nice iron play and some nice putting."

There was a sellout crowd to see the three biggest draws in the game go toe to toe.

McIlroy played the first few holes in textbook fashion, two-putting from 24 feet at the 10th as Woods almost stiffed his approach and 27 feet at the 165-yard 11th.

He got up and running at the 461-yard 12th, where Woods was 100 yards further back after hitting a lay-up off the tee, blasting a 354-yard drive over the bunker on the left.

McIlroy’s birdies

No. 12 Lob wedge, 86 yards, to 1 foot, 10 inches

No. 13 3-iron second shot into bunker from 250 yards, bunker shot to 2 feet, 3 inches

No. 14 6-iron, to 26 feet, 4 inches

No. 15 9-iron, 131 yards, to 9 feet, 3 inches

No. 2 7-iron, 172 yards, to 14 feet, 1 inch

No. 5 3-iron second shot from 273 into greenside bunker, bunker shot to 11 feet, 4 inches

No. 9 Sand wedge, 105 yards, 18 feet, 8 inches

A flip wedge from 86 yards finished 22 inches from the cup and after tapping that in, he got up and down from greenside sand short of the pin at the 628-yard 13th and splashed out to two feet to go two-under.

He then fired a towering approach 26 feet beyond the flag at the 230-yard 14th and his right to left breaking putt back down the hill never looked anywhere else but the middle of the hole to tie with Zalatoris for the lead on three-under.

Woods also made two there to remain one behind, but the 15-time major winner struggled with his injured leg and made six bogeys and a birdie in his last 13 holes to card a 74 as Spieth had 33 putts in a 72.

"The game is played very differently now, and it's very aggressive," Woods said. "We were talking about it today, Joey and I, the days of the Lee Janzens and the Scott Simpsons and the Faldos of the world, playing that kind of golf is gone. You go out there and hit driver a lot, and if you have a hot week, you're up there."

The Holywood star was in the right rough at the 15th and blocked out slightly by a large sycamore.

But he went down the shaft and cut his 133-yard approach to nine feet pin-high right and brushed in his fourth birdie in a row to take the solo lead on four-under-par.

He drove into sand left at the 532-yard, par-four 16th but muscled his 200-yard recovery to the front edge and made a simple par.

After almost making a 16 footer from the fringe at the 17th, he found rough left at the tough 18th, which was playing back into a strong breeze but found the back fringe and tickled his 35 footer down to seven feet above the hole.

The putt was a quick one, but he made it look easy as he slotted it home, then birdied the 508-yard second by rolling in a 14 footer.

He had to make a six-footer for par after coming up short at the third, but after missing an eight-footer for another birdie at the fourth, he took on the trees and the out of bounds on the left and reduced the 665-yard fifth to a 369-yard drive and a three-iron to the front bunker followed by an 11-foot putt to ease to six-under and three clear.

He was bogey-free since the 12th hole in the third round of the Masters but eventually dropped shots at the 218-yard sixth, where he missed his tee shot in the right rough and the 248-yard eighth, where he was bunkered left, before closing with another birdie.

"I think just happy with when you get off to a good start like that, sometimes you can maybe start to be a little careful or start to give yourself a little more margin for error, but I stuck to my game plan," McIlroy said

I" stayed aggressive, hit that driver up 4, took an aggressive line on 5. Yeah, I stuck to what I was trying to do out there, which I was pleased with.

"Then, if anything, obviously the two bogeys on the par-3s on the front nine, but it's very easy to make bogeys out here. You get yourself just a little bit out of position, you catch a little bit of grain around the green, it's tricky.

"I didn't encounter too many of those tricky scenarios today, but it can certainly be tricky. You get yourself out of position here, you just try to make a 4 or a par and run to the next."

If it was a great morning for McIlroy, it was one to forget for Harrington, who struggled from the moment he found the creek from the tee at the second and made a double-bogey six.

The 2008 champion would birdie the third and 12th from inside three feet, but he also made another seven bogeys, getting up and down just twice as he found eight greenside bunkers and had 33 putts in a 77.

"It was one of those days I compounded everything and everything that could go wrong went wrong," Harrington said. "I hit a couple of very good shots that plugged in bunkers and it seemed to be one of those days.

"I didn't hole any putts and it added up to momentum in the wrong direction. I didn't get anything right. My good shots didn't work out right and the bad shots I didn't recover from.

"It was as simple as that. I wish it was better, but I will have other days like it.

"They are terrible bunkers, but I hit them all well out of the bunkers except for the two plugged lies. One of them I actually hit close.

"But I actually hit excellent bunker shots. It was just one of those days. They didn't cost me anything. I played them all well.”

McIlroy may well have lucked out with the weather with the forecast for high winds in the morning and calmer conditions in the afternoon.

Of the 26 players under par after round one, 17 came from the early wave.

The best rounds of the afternoon came from former PGA champion Justin Thomas who shot a three-under 67s to share fourth place with Matt Kuchar and Mexico’s Abraham Ancer as the top three in the world struggled, No 1 Scottie Scheffler posting a 71 as Jon Rahm shot 73 and Collin Morikawa a 72.