‘No one gave a sh*t’: Rival angered by raucous crowd which mobbed Mickelson as he was crowned oldest ever Major winner (VIDEO)

Phil Mickelson became the oldest ever Major winner after claiming the PGA Championship title amid wild scenes as a throng of fans mobbed the US veteran on Sunday – causing frustration from rival Brooks Koepka.

Mickelson carded a one-over-par 73 for his final round at the Ocean Course on Kiawah Island, but that was enough to see him finish two shots clear of fellow American Koepka and South Africa’s Louis Oosthuizen.

Aged 50, Mickelson picked up a sixth Major and a first since 2013 – also overtaking the mark for the oldest person to win one of golf’s biggest prizes.

The previous record was held by Julius Boros, the American who won the PGA Championship at the age of 48 back in 1968.

Mickelson’s final round was followed by a mass of raucous fans in South Carolina as they roared on one of golf’s most famous faces to an improbable victory.

There were particularly wild scenes around the fairway on the 18th when Mickelson found the green to set up his coronation, with fans swarming him and his caddie and also engulfing Koepka and his bagman.

Mickelson battled his way through the masses before emerging and raising his hand in acknowledgement, although rival Koepka – who had still be chasing an unlikely turnaround on the final green – was concerned by the furor.

The American later said he'd been struck in his knee, which is still delicate just two months after undergoing major surgery.

“It would have been cool if I didn't have a knee injury,” said the two-time former PGA Championship winner.

“I got dinged a few times in the knee in that crowd because no one really gave a sh*t, personally.

"But if I was fine, yeah, it would have been cool. It's cool for Phil. But getting dinged a few times isn't exactly my idea of fun."

“I don't think anybody really understands until you're coming out of surgery how – I mean, even when I was doing rehab and there's five people kind of standing by your knee, you get a little skittish," he added. 

“Like I don't mind waiting or being in that crowd but getting my – I don't know, it felt like somebody tried to, I don't know what the deal was, but it's what it is. [I'll] be putting it in ice today. It feels like sh*t right now.”

Koepka missed out on a third US PGA Championship after victories in 2018 and 2019. © USA Today Sports

The 31-year-old star said his caddie, Ricky Elliot, had been hit in the face during the scenes.

"Ricky stopped unintentionally because he got drilled in the face, and then I got hit because he got stopped so quickly. There were so many people around.”

The PGA guidance for fans had stated that they should "respect [players'] space and watch your distance" and "avoid unnecessary touchpoints and large crowds" – although members of the commentary team in one clip posted online declared that staff had “lost control of the scene.”

"I've never had that experience and to see that, to feel that kind of excitement and enthusiasm, and be at the forefront of that, was pretty special,” Mickelson himself said, admitting that it was also “unnerving.”

After Mickelson’s triumph – his second PGA Championship – praised poured in from fellow golfers, including 15-time Major winner Tiger Woods, currently recuperating from his serious car crash earlier this year.

“Truly inspiration to see [Phil Mickelson] do it again at 50 years of age. Congrats!” Woods tweeted.