Golfing guru Butch Harmon believes Rory McIlroy made "a big mistake" when he allowed Bryson DeChambeau to get into his head in a battle to be the game's longest driver.
DeChambeau's stunning form since he bulked up physically and became the biggest hitter in golf last year encouraged four-time Major winner McIlroy to strive for more yardage on his drives.
Yet the coach who worked with Tiger Woods as he claimed a host of Major titles has suggested McIlroy was misguided to try and change his game to adapt to the threat posed by DeChambeau.
Speaking at a Sky Sports event, Harmon revealed McIlroy came to him last November to discuss the changes he was looking to make to his game and his advice was simple.
"I was surprised when Rory said what he said by trying to catch Bryson in distance and in my view, it was a big mistake," Harmon stated.
"The beauty of Rory is he is brutally honest about himself because you wouldn't hear a lot of great players coming out and saying that.
"I spent some time with Rory at the end of last year just giving him a different opinion and that's what this game is all about. It's good to be open-minded and I admire Rory for that.
"Rory is already one of the best drivers in the game and he has a swing that is geared to driving the ball in play and long. He doesn't need to go after DeChambeau and hit the ball longer than him.
"He needs to go back to playing golf, the basic fundamentals of what made him so good. This chasing Dechambeau distance-wise was so wrong as he is a beautiful driver. It got into his head, into his swing and into his game.
"There seems to be a drive for players to reach for more distance, but if you look at players like Dustin Johnson, John Rahm and Justin Thomas and while they are long hitters, they are not trying to jump out of their shoes.
"They just play their game and Rory needs to realise that's why he needs to do."
McIlroy will make another attempt to win the only Major championship to elude him when he returns for another crack at The Masters in the coming days, with Harmon suggesting his more to call on the advice of highly respected swing coach Pete Cowen was a shrewd move.
"Working with Pete is a good combination because he is one of the best golf coaches in the world, but how will he take on the new swing thoughts heading into a Major," questioned Harmon.
"In golf, changes take time and we need to wait and see how committed Rory will be to the changes Pete wants to introduce and how confident he is to put those into play at Augusta.
"Knowing Pete, I'm sure he's getting that distance issue out of his mind and that will help him."
Harmon does not believe DeChambeau's prodigious length off the tee will give the US Open champion an advantage at Augusta, as he suggests Dustin Johnson is favourite to win again after he claimed his first Masters Green Jacket in the re-scheduled event last November.
"The DeChambeau debate is great for golf because it gets us all talking and I'm fascinated to see how long he can keep swinging like that," he added.
"The human spine just isn't built to cope with the torque he gets in his back and I don't know his left ankle copes with the pressure he is putting through it, but it's a great talking point for golf.
"Yet for me, Augusta is not a course where DeChambeau's length gives him an advantage as distance is not so important.
"If it is hard and fast, as we are being told it will be, it will be even tougher, so maybe and maybe Bryson needs to take a page out of Dustin Johnson's book and play a little more conservative.
Second shot course
"Everyone gets wrapped up with distance at Augusta and if you can drive the ball long and in the fairways, then the par 5s are easier, but this is a second shot course.
"This is not a course where you shoot at flags. You aim for areas on greens and allows the slopes to take it towards the flag, so you need 100% on with your iron play.
"Your distance control, shot control, trajectory of the ball has to be on to succeed at Augusta. Then you have to putt great.
"Dustin showed when he won the Masters in November that he had all of that in his locker and that's why DJ is the man to beat again."
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