Sister exposes nervous mum's hilarious texts to Phil Mickelson

American Phil Mickelson now has the honour of being the oldest major champion in the history of men's golf but that doesn't mean his mum isn't like any other.

In fact, before 'Lefty' sealed his place in golfing history by winning the PGA Championship at the age of 50, his mother Mary was experiencing her own wave of emotions during the final round.

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Much like the rollercoaster final round battle between Mickelson and Brooks Koepka at Kiawah's Ocean Course, the six-time major winner's mum was also experiencing a rollercoaster of emotions watching from home on TV.

Tina Mickelson, Phil's sister, fielded what she called "nervous texts" from Mary all afternoon. She shared one of their exchanges on Twitter, which was absolutely adorable.

In what could be the most 'mum' text ever, Mary takes the more formal approach by referring to her son as "Philip", when the world knows him simply as "Phil".

And Mary knows what mothers everywhere know: no matter how old they are, kids don't listen to their mothers.

Since Mary didn't think her son would listen to her advice, she asked Tina to text him instead.

However, Tina knew the real way to get through to Phil was via his caddy - which just so happens to be their brother, Tim.

Tina didn't reveal whether or not she actually texted Tim, but she did share an exchange they had at a recent family dinner where Phil and Tim warned the whole family that his victory on Sunday might be coming.

'Lefty' heaps praise on Aussie coach

Mickelson heaped praise on his Australian coach Andrew Getson after becoming the oldest major championship winner in history.

Mickelson, less than a month shy of his 51st birthday, smashed the record previously held by Julius Boros, who won the 1968 PGA at 48.

Getson, a former Australasian and Asian Tour player, has worked with the now six-time major champion since 2014 having met him in Scottsdale, Arizona while part of the Grayhawk Golf Club.

He's been a significant presence by the veteran's side on the US PGA Tour since.

"His guidance has been invaluable, really, to get me back to playing at the highest level because I was striking it very poorly when we started working together years ago, and I had a great performance (after that) at the 2016 Open Championship where I lost to Henrik Stenson," Mickelson said after his famous win.

"When he's out here with me, he's able to keep me on track right away if I make a few errors.

"He's really helped me get my ball-striking back and as I'm starting to focus a little bit better, you're starting to see the results, but he has been getting my swing there for some time now.

"He is a tremendous instructor because of his ability to simplify it. He has helped get my swing on plane from parallel to the ground.

"Obviously I have a long swing but rather than try to change that when it's halfway down ... he helped me develop and refine my feel and touch and simplify it. He doesn't cloud my head with a lot of things."

Getson notoriously shies away from media when it comes to his work. He prefers his clients get the attention.

"It's a special and emotional day," he reluctantly told AAP in the aftermath.

"He's worked really hard for this and deserves every accolade he gets."

Getson joins Cameron McCormick and Colin Swatton as Australian coaches to guide players to major championship success in the past six years.

McCormick helped Jordan Spieth to three majors (2015 Masters, 2015 US Open, 2017 British Open) while Swatton was at the helm when Jason Day won the 2015 PGA.

with agencies

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