Phil Mickelson and Zach Johnson came to the 7th hole all square in their match against Adam Scott and Jason Day. They left two down. Do what? It's true.
Mickelson errantly played in incorrect golf ball before picking it up halfway through the hole and not finishing out. Johnson was beaten by the International team.
The rule Mickelson violated is called the "one ball" condition, and it applies specifically to match play. Here's what the USGA rule says.
i) "One Ball" Condition
During a stipulated round, the balls a player plays must be of the same brand and model as detailed by a single entry on the current List of Conforming Golf Balls.
Note: If a ball of a different brand and/or model is dropped or placed it may be lifted, without penalty, and the player must then proceed by dropping or placing a proper ball (Rule 20-6).
Mickelson apparently played the 7th hole with a different type of ball than he started the round with. This rule doesn't apply in the alternate shot format. The penalty is as follows.
Match play - At the conclusion of the hole at which the breach is discovered, the state of the match is adjusted by deducting one hole for each hole at which a breach occurred; maximum deduction per round - Two holes.
But here's the rub. Mickelson didn't have to stop playing the hole. He could have played out the hole instead of letting Johnson go alone. Johnson lost and then the extra hole penalty was tacked on.
According to Golf Channel, Mickelson was actually told to pick up his ball by a referee. According to Steve Sands of Golf Channel, the head referee for the Presidents Cup apologized and said it was "committee error." Yeah, no kidding.
The referees also took responsibility in this release from the Presidents Cup which also said there's essentially nothing that can be done after a player picks up his ball.
Here you go pic.twitter.com/KWsxrCSRmA
— Doug Ferguson (@dougferguson405) October 9, 2015
"Phil assumed the one ball rule was not in effect," said US captain Jay Haas. "It was a mental error. He was told he was disqualified from the hole but I'm not too sure if that was the correct ruling."