CNN  — 

Four-time major winner Rory McIlroy is in a slump of form, and nothing embodied that more than his drive on the fifth hole at the WGC Matchplay on Wednesday.

The big-hitting Northern Irishman walloped his drive, leaning on his club when he realized it was hooking dramatically to the left, with the ball eventually finishing in someone’s swimming pool in a nearby house.

The wayward drive wasn’t the only time McIlroy’s ball took a splash during his match against Ian Poulter, as he had to take a drop on 13 after his chip across the green rolled into the water.

Finding the water twice was just one of a litany of errors McIlroy made in his opening group game at the PGA Tour event at the Austin Country Club.

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McIlroy plays his shot on the sixth tee in his match against Poulter.

Having fallen three down after five holes, he was eventually thrashed 6-and-5 to Englishman Poulter.

The 31-year-old, who has had struggles with his swing and has recently employed renowned coach Pete Cowen to his team, declined to speak with the media after his round.

McIlroy has not won a PGA Tour event since the World Golf Championships-HSBC Champions in November 2019, and his ranking has plummeted from No. 1 to No. 11 in the official world golf rankings.

He now faces American Lanto Griffin in his next group match with his final match against Australia’s Cameron Smith, who finished joint second at last year’s Masters.

Poulter, the 60th of 64 seeds at the tournament, sympathized with McIlroy’s struggles and believes the hiring of Cowen will help rejuvenate his Ryder Cup teammate.

“Obviously, Pete’s going to be working exclusively with Rory on his game, (and) I think there’s a couple of areas of his game which I’m sure he wants to kind of firm up a little bit,” Poulter told the media afterward.

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McIlroy lines up a putt on the fourth green in his match against Poulter.

“And obviously he missed a couple of tee shots left. From that point, he was trying to hit, a kind of, a bit of a hold-up cut. But it’s Rory, it doesn’t take a lot for Rory to spark up pretty quickly and I wasn’t surprised with anything, I just felt that I had done a pretty decent job of putting him under pressure. I made it difficult for him.”

The 64 players at Austin are split into 16 groups of four with only the group winners advancing to the knockout stages at the weekend.

Elsewhere, there were straightforward wins for world No. 1 Dustin Johnson, Jon Rahm and Bryson DeChambeau, among others.