The PGA champion shot a 10-over par 80 on the first day at The Open, his worst opening round ever at the championship, leaving him 16 shots behind the leader Louis Oosthuizen.

Phil Mickelson Sets Unwanted Record At The Open

Phil Mickelson isn’t afraid of making history.

This year, he became the oldest Major champion in the history of golf at the PGA Championship in May, winning the Wanamaker Trophy aged 50.

Ten years ago, Phil Mickelson finished tied for second place at the 140th Open Championship at Royal St. George’s, losing out to a triumphant Darren Clarke in awful weather conditions.

Two years on from that, Mickelson claimed his first – and to date only – Claret Jug at the 142nd Open Championship at Muirfield, finishing three shots clear of Henrik Stenson.

Yesterday, Phil Mickelson shot his worst opening round at The Open – ever.

It was just his second round in the 80s ever – he shot 85 in the 3rd round of the 1993 Open at Royal Birkdale – and he looked as confused as the rest of us as he walked off the 18th green yesterday.

Yesterday was Mickelson’s 93rd round in an Open Championship and easily one of his most shocking to date.

Before the start of play on Friday, lefty sat in a tie for last place – T156th out of 156 starters.

After parring the first two holes of his round, Mickelson bogeyed the next three holes and was never able to recover from there.

Related: Open Championship Full Leaderboard

Despite moments where he seemed to settle, he couldn’t string a run of pars together to stop the rot.

Intermittent bogeys at the 8th, 9th, 13th, 15th and 16th left him reeling and a final double bogey on the 18th hole left him with eight bogeys, one double bogey and zero birdies.

A glum looking Mickelson tapped in his 80th shot of the day, handed his putter back to his brother Tim, shook hands with his playing partners, politely tipped his hat to the crowd and quickly made his exit to try and make sense of what just happened.

The oldest Major champion in golf’s history had arrived at Royal St. George’s in plenty of time – with his last event two weeks ago on the PGA Tour in Detroit – and was seen plenty of times during the practice round, sporting a fetching pair of pastel blue shorts, so it’s hard to explain just where this round came from.

He tees off on Friday at 9:47am BST and – while the cut mark seems an almost impossible target – no doubt Phil will want to right the wrongs of Thursday and leave Royal St. George’s off the foot of the leaderboard.