That’s not how Shane Lowry drew it up.

After an excruciating missed shot at the British Open on Friday, the Irish former Open champion took out his anger on one of his clubs, snapping it over his neck as his second-round performance took a dismal turn.

Lowry, who won The Open in 2019, is in danger of missing the cut as he sits six over par in the second round and seven over for the tournament.

The Irishman, who finished Thursday’s first round in Liverpool at +1, tumbled 61 places down since the start of play on Friday, entering a tie for 109th place.

It’s been a disappointing season for Lowry, whose best finish in 2023 came when he finished fifth at the Honda Classic in February.

Lowry, whose other career win came at the Bridgestone Invitational during the 2014-15 season, last made waves at a major tournament when he finished tied for third at The Masters in 2022.

Following his title at The Open in 2019, he held on to the Claret Jug for two years because the tournament was canceled due to COVID-19 in 2020.

“You never get sick of hearing that you’re the Open champion, but I’m kind of ready to defend it,’’ he told The Post in 2021. “I’m ready to go and play in the Open again and I’m looking forward to it. I look back on Portrush with incredible memories and fond memories and something that I’ll have no matter what I do for the rest of my career. I’ll always have that.”

Lowry finished 12th in 2021 at the British Open and got worse last year, ending his run in 22nd place.

At his tournament win in 2019, Lowry became the first golfer since 1996 to finish over par in the final round as rain and wind rocked the course, finishing with a 1-over 72.

“I can’t believe this is me standing here,” Lowry said as he held golf’s oldest trophy. “I can’t believe this is mine.”