The PGA Tour’s historic deal with LIV Golf cast a shadow over the US Open at Los Angeles Country Club and Phil Mickelson, who joined the Saudi-backed series last year, was an apparent target of some boos on Thursday.

The fan was on the rail of the grandstand on the 18th hole and was interrupting «Lefty» for more than 30 seconds, according to Sports Illustrated. The topics of the harassment were Mickelson’s deal with LIV Golf and an alleged endorsement with Victoria’s Secret.

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Phil Mickelson swings onto the green on the sixth hole during the first round of the US Open at the Los Angeles Country Club on Thursday, June 15, 2023. (AP Photo/Lindsey Wasson)

Dylan Dethier of Golf Magazine took a photo of the alleged troublemaker, who was wearing a hat.

The incident caused Mickelson to briefly lose concentration, but he finished his round with a 69 and tied for 25th place. Xander Schauffele and Rickie Fowler finished with 62 in the first round and set a record for the lowest score for a US round. Open in the history of the tournament.

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Phil Mickelson changes

Phil Mickelson watches his tee shot on the 18th hole during the US Open at the Los Angeles Country Club on Thursday, June 15, 2023. (AP Photo/Matt York)

«I played well. I took a few swings down the stretch, I took two bad swings that cost me a few shots,» Mickelson said, via Yahoo Sports. «But I took a lot of good shots today. It’s a decent start, and tomorrow morning I have a chance to go out there and shoot a good, solid round to be in position for the weekend.»

As for the LIV Golf deal, Mickelson said he didn’t want to talk about it yet.

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Phil Mickelson gives thumbs up

Phil Mickelson gestures during the first round of the US Open on Thursday, June 15, 2023. (AP Photo/Matt York)

«I don’t want to detract from this tournament and where I am right now,» he added. «I’m playing well, I want to be in contention.»