Playing at the Charles Schwab Challenge in Texas on a sponsor exemption just four days after finishing in a tie for 15th at Oak Hill, Block carded an 11-over 81 that left him in 120th position after the first round – plumb last and four shots behind Rory Sabbatini in 119th.
He is 19 shots behind leader Harry Hall at eight-under.
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His round wasn't without thrills though. A wayward tee shot on the par-4 10th hole saw his ball come to rest on a bridge. He punched it back out to the fairway and played a sensational pitch to about 40cm to save par.
Block is a club professional at a public course in California. He can usually be found in a pro shop or on the range giving lessons, not on the PGA Tour.
He opened with three bogeys in a row, and closed with three double-bogeys in his last four holes.
Block said this was the round he was expecting to have last weekend.
"If you are a golfer, you've had the day I've had," he said after the round.
"You understand the facts of where the lies aren't good and the trees are in your way every time. Even your good shots are bad, your bad shots are worse – it is what it is.
"I'm going to live with it. I thought it was going to happen that third or fourth round last week at Oak Hill, and it never happened. It happened now, and I wasn't surprised by it, to tell you the truth."
Block has another sponsor exemption to play at the RBC Canadian Open next week.
After his performance at the PGA Championship, Block made appearances on podcasts, breakfast TV and even received a text from Michael Jordan.
Despite the almost impossible task in front of him to play on the weekend, Block remained upbeat.
"I'm looking forward to coming out tomorrow and playing a great round and giving it everything I have," he said.
"I've shot 58, and I've shot a 59 in my life, and since what I had today, I wouldn't be surprised if I did it.
"So if I do, cool. If not, I'll be seeing my kids and my wife tomorrow night in California. It's all good one way or the other."
Min Woo Lee is best of the Aussies in a 15-way tie for seventh at three-under, five shots off the lead. Cam Davis is a shot further back at two-under.
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