British OpenJuly 14, 2016

Down goes Bones! The best part of Phil Mickelson's 63 might have been his caddie's reaction

TROON, Scotland -- Golf fans saw just how strong the bond is between Phil Mickelson and caddie Jim "Bones" Mackay when Mickelson won the 2013 British Open. It was Bones, and not Phil, who had tears flowing on Muirfield's 18th green as soon as Mickelson wrapped up the title.

And on Thursday, Lefty's longtime caddie showed his unbridled emotion and passion once again. As his boss came painfully close to doing something no golfer has ever done, Bones dropped to the ground like he'd been hit by a shot from the group behind him. Check it out.

And here's another look:

Ernie Els' caddie looks genuinely concerned for Bones' well-being.

We can report Bones eventually got up and made his way to the scoring area, but he looked devastated. Later, Mickelson talked about the discussion he and his caddie had before the birdie attempt.

"I said, 'I need your best read. I don't know if you know this...' he says, 'Oh, I know.' So we're on the same page, and we took a look and we came up with a really good read," Mickelson said. "I hit a good putt on the right line with the right speed and unfortunately the (62) curse, and it hit me hard."

It might have hit Bones even harder.

RELATED: Watch how close Phil came to shooting 62


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