Seamus Power eagled at the last to open with a stunning 65, but Pádraig Harrington was even happier as he celebrated the return of Rory McIlroy's "swagger" with a super 66 in the AT&T Bryon Nelson.

The Dubliner hit all 18 greens as made an eagle and four birdies on a day of hot scoring at TPC Craig Ranch to lie tied 19th, three shots behind playing partner JJ Spaun and Jordan Spieth, who bang in a 55-foot eagle putt at the 18th for a 63 and a one-shot lead over Rafa Cabrera Bello, Aaron Wise, Doc Redman and Joseph Bramlett.

Scores

Harrington is looking to sharpen his game for next week's PGA Championship, and as European Ryder Cup skipper, he was thrilled to see McIlroy get back to winning ways with his victory in the Wells Fargo Championship at Quail Hollow.

"Look, I was pleased," he confessed. "I won't say I wasn't. It certainly wasn't unexpected by me. Rory's always been an ebb and flow player. When he starts playing well, he plays even better.

"For me, I know it's selfish, and I am only being a bit facetious, but I wasn't unhappy with his form because I was thinking he's hanging onto his form for later in the year.

"You know, clearly Rory can play well all year. The way I look at it is that win last week brings back a bit of that swagger that we all need on the golf course. Rory is a very dangerous player with that. Hopefully, he'll be a very dangerous player for at least -- for five more months."

He took full advantage of preferred lies, and after following birdies at the 14th and 16th with an eagle three at the 18th, where he holed from 48 feet, he picked up further shots at the fourth and sixth on the back nine.

"You know, I hit 18 greens in regulation. You know, I probably haven't done that a handful of time in my whole year, so that was nice. The course is generous. With the moisture, the rain that we've had, it softened it up a bit.

"So I think the greens are actually in too good condition. It's absolutely perfect. Fairways are perfect. Greens are perfect. Bit of placing, you know, kind of leaves you shooting 6-under par like me and feeling like I should have done a little bit better.

"I drove it pretty straight. I changed my routine a bit this week, so that was nice. I was better. I was definitely better. So something like that, you know, I did some practice at home. I really struggled my whole career with that transfer from the range to the golf course. Really find it hard.

"It's a different rhythm on the range than on the golf course, so I kind of went -- instead of trying to go back to what is perfect for me on the course, I went with what I do on the range. I went more with my practice routine rather than what I would consider would be my ideal routine on the course.

"I always like to play the week before a major. I had intended to come over a couple weeks earlier, too, so I was meant to be over at Valspar, and I ended up not coming. So it was meant to be a run of events here. I've always enjoyed the Byron Nelson at the other course, but I really enjoyed actually Trinity Forest last year. It's been a good event for me, one I would like to come to. You know, the week before a major, it's ideal for me to come and play."

Power was tied for sixth on seven-under after he birdied the first, ninth, 11th, 12th and 14th before watching his eagle chip drop on the final roll at the 18th.

"I actually didn't hit the best tee shot," said Power, who is 195th in the FedEx Cup standings after making four cuts from nine starts in the 126-150 category. "I kind of pushed it a little bit to the right but got lucky enough with the lie that I was able to get it just short of the green, and then obviously with placing, I was able to have a perfect lie.

"I hit it very nicely. I knew as soon as I hit it, it would be close, but to see to fall in was a huge bonus."

As for his form, he said: "I knew my game was in pretty good shape, but you still you have to put the scores on the board. I've played well last two weeks but just haven't put the scores together, so it was nice to see that."

Spieth made seven birdies before knocking in that eagle putt at the 18th to share the lead in his first start after being forced to quarantine after contracting COVID-19 shortly after the Masters.

"It was my third round I played since the Masters, first-round walking since the Masters," Spieth said. "Played nine holes walking on Tuesday. But I noticed it in my legs. It's just one of those things. It's like with basketball players. Basketball shape is nowhere near golf shape, but when they get out, miss ten games, it takes a couple games to get your legs back.

"For me, I noticed it in my swings coming down the stretch. Just got lazy in my lower body. On 18, I just said, This is the last one you got to do today. Let's give it everything you got, and roasted a 3-wood and capped it off with the putt."

Hideki Matsuyama shot 68 in his first start as Masters champion to share 58th but Bryson DeChambeau was disgusted with a three-under 69 that left him tied 75th.

Brooks Koepka is also struggling to make the cut after a 71 left him joint 116th.

At the Betfred British Masters at The Belfry, 2017 champion Paul Dunne continued his return to form, carding a three-under 69 to share 16th on three-under.

Scores

He's just four shots behind Richard Bland (69) and Scottish duo Robert MacIntyre (66) and Calum Hill (70), who lead by a shot on seven-under.

Cormac Sharvin shares 48th on level par after a 71 while Jonathan Caldwell fired a 69 to make the one-over cut on the mark as Niall Kearney (77) and Colm Moriarty (75) missed out on six and nine-over, respectively.