Rory McIlroy is known to speak his mind and he thinks Brooks Koepka has taken honesty to another level with his sledge of PGA Championship rival Dustin Johnson.
The Northern Irishman admits he was "taken aback" by Koepka's verbal dig at Ryder Cup teammate Johnson during the year's first major - won by Collin Morikawa.
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Koepka went into the final round of the major two behind former US Open champion Johnson - chasing a fifth major title in 11 starts.
When asked about his chances of winning a third straight PGA Championship after his third round effort, Koepka raised eyebrows with a response deemed disrespectful towards his fellow American.
"A lot of guys on the leaderboard I don't think have won (a major)," Koepka told CBS when asked about his chances after the third round.
"I guess DJ (Johnson) has only won one. I don't know a lot of the other guys that are up there."
McIlroy was quizzed about the comments after his final round 68 saw him finish in a tie for 33rd at two-under par.
The World No.3 suggested it was a little disrespectful of Koepka to talk down the fact Johnson had “only won one” major title.
"It's a very different mentality to bring to golf that I don't think a lot of golfers have," he said.
"I was watching the golf last night and heard the interview and was just taken aback a little bit by what he said and whether he was trying to play mind games or not.
"If he's trying to play mind games, he's trying to do it to the wrong person.
"I don't think DJ really gives much of a concern (about) that.
"I certainly try to respect everyone out here. Everyone is a great player.
"If you've won a major championship, you're a hell of a player.
"Doesn't mean you've 'only' won one; you've won one and you've had to do a lot of good things to do that."
McIlroy then delivered his own zinger to Koepka, in defence of Johnson's record as one of the world's best golfers.
"I mean, (it's) sort of hard to knock a guy (Johnson) that's got 21 wins on the PGA Tour, which is three times what Brooks has," he said.
Morikawa wins first major after epic final round
Fiery comments aside, it was a final round to treasure for Morikawa, who claimed his maiden major title in style.
Morikawa says he will embrace the spotlight after announcing himself as golf's newest superstar with a breakthrough major victory for the ages.
The American capped his meteoric rise since turning professional 14 months ago by beating out a field of golf's biggest names to claim a two-shot victory.
The 23-year-old American, playing just his second major, shot a final round 64 for a 13-under-par total while England's Paul Casey (66) and American Johnson (68) were runners up at San Francisco's TPC Harding Park.
It was the lowest final round by a PGA champion since Australia's Steve Elkington fired 64 to win the 1995 edition.
Australia's Jason Day (66) and Americans Matthew Wolff (65), Bryson DeChambeau (66), Tony Finau (66) and Scottie Scheffler (68) were tied fourth at 10 under.
"It's amazing," Morikawa said after being handed the Wanamaker Trophy and $US1.98 million ($A2.76m).
"It's been a life goal (to win a major), as a little kid, watching all these professionals, and this is always what I've wanted to do."
Morikawa joins an illustrious group of greats to have won a major before the age of 24 including Tiger Woods, Jordan Spieth, Jack Nicklaus, Seve Ballesteros and Rory McIlroy.
"Any time you're in the conversation of the greats, Jack, Rory, Tiger, you're doing something well," Morikawa said.
with Yahoo Sport staff