The famed lefty had to place a rush order on a new eight iron after a freak accident on the 12th hole during Thursday's first round.
Mickelson was hitting out of a fairway bunker at TPC San Antonio when the shaft of his iron shattered just above the hosel, sending the club head spinning after the ball. Television microphones picked up his reaction: "What the heck?"
"It was just a weird thing," he said. "It happens. It's part of the game, I guess."
Though he bogeyed that hole, Mickelson played well enough to finish the day at two-under and explained that Callaway was sending out a replacement.
As an early starter on Friday, he stood tied for fourth through several holes of the second round.
Charley Hoffman held the lead in Texas at five-under.
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