Golfing legend Jack Nicklaus joined those hailing Rory McIlroy after the 22-year-old re-wrote the record books in winning the US Open by eight shots.
"He's ahead - and his score is way ahead of my pace," said Nicklaus, almost five months older than McIlroy when he won his first major in 1962.
"I think this kid's going to have a great career - I don't think there's any question about it."
Compatriot Graeme McDowell added: "He's potentially the next Tiger Woods."
Some of the sport's biggest names have been paying tribute to the brightest youngster on the circuit.
Jack Nicklaus - 18-time major winner
"It was obviously an unbelievable performance. I thought he played just fantastic golf. It is so great to see a nice young man play well, to do well.
"We are all aware that he has been there before, but he showed that he learned from his mistakes, and he showed that he knew how to play the last two days with a big lead. Not only did Rory know how to play with a big lead, he played it confidently, played it smartly, and he never put himself in position to be in trouble.
"He's humble when he needs to be humble and confident when he needs to be confident. I like his moxie - he's cocksure and I like that. You've got to have that.
"He obviously had a couple of disappointments at the Masters and last year's Open [McIlroy started 63-80 at St Andrews and finished with an 80 at Augusta], but I didn't think that was going to happen again and it hasn't."
Graeme McDowell - 2010 US Open champion, also from Northern Ireland
"I first heard about him when he shot that 61 at my home course in Portrush.
"You hear rumours about people and good players come and go, but this kid was something a bit special.
"It's great to see him out there fulfilling his potential. He's been like an accident waiting to happen.
"He's been groomed to be a superstar and he'll handle it very well. It's not a monkey off his back, it's a gorilla. He could go on and do some big things.
"He's probably the best driver of the ball I've ever seen. We nicknamed him the 'BMW' because he is the 'ultimate driving machine'.
"Nothing this kid does ever surprises me. He's the best player I've ever seen.
"I didn't have a chance to play with Tiger when he was in his real pomp, but this guy is the best I've ever seen, simple as that.
"He's great for golf. He's a breath of fresh air for the game and perhaps we're ready for golf's next superstar and maybe Rory is it."
Padraig Harrington - Three-time major winner
"If you are going to talk about someone challenging Jack's record there's your man.
"Winning majors at 22 with his talent - he would have 20 more years, so probably 100 more majors in him where he could be competitive.
"It would give him a great chance.
"Rory has proved in playing the majors so far that he is comfortable making the scores."
Phil Mickelson - Four-time major winner
"You can tell that Rory has had this type of talent in him for some time now, and to see him putting it together is pretty neat to see."
Luke Donald - World number one
"As I've said before, I think he has probably the most talent I've ever seen from a golfer.
"It's lovely to watch him play, he has such a fluid motion and he hits it far."
Michael Bannon - McIlroy's coach
"Rory has always had the potential to play at this level. He's done a lot of work this year on his body.
"We look at the swing a bit more often now to make sure the good swings are in place more often.
"He's developing a level of consistency now that we haven't seen before."
Jason Day - 2011 Masters and US Open runner-up
"The way he's playing out there, it's almost Tiger-esque. To have the lead that he has in the US Open is pretty ridiculous and at such a young age.
"Obviously the next generation is starting to kick up now and he's the guy that's leading it."
Steve Stricker - World number four
"He's got a lot of talent and he's only 22. He's got the world in front of him really.
"His game looks flawless. His swing looks great. I think it looks just as good as when Tiger was in his prime and swinging at it at his best. You just don't see any flaws.
"I think fundamentally he's as good as we've seen ever in my era, take Tiger Woods out of it.
"When Tiger was going well, that's as good as I've ever seen. I think Rory is in that same boat.
"His swing is mechanically sound, and he's got a great short game and he putts it well, and he's long. So he's got all the tools. So it's pretty impressive."
Brandt Snedeker - finished tied for 11th at Congressional
"Rory has more talent in his pinky than I have in my whole body."
Davis Love III - American Ryder Cup captain
"He's about 27 in golf years. He's very polished on experience.
"I don't think we've seen a rookie come out with his composure and be ready to play on our Tour right away like he is."
Rafael Nadal - Tennis world number one
"What he's been doing is really something unbelievable. He's probably got one of the nicest swings in the world, if not the nicest.
"It's been fantastic to watch what he's been doing in this tournament. In my opinion, right now he's playing at a different level to the rest. So for sure he is an inspiration. I admire him a lot."