British Open GamblingJuly 15, 2016

British Open odds: Vegas makes Phil Mickelson an overwhelming favorite after first-round 63

TROON, Scotland -- It's officially Phil Mickelson's British Open to lose.

After a scintillating 63 (really a 62.5) on Thursday, Mickelson teed off early Friday with a three-shot lead. And his advantage, according to the Westgate Las Vegas Superbook is even greater.

Mickelson began the tournament at 40 to 1 to claim the claret jug. He's now a big favorite at 4/1.

"Well, one of the biggest challenges is when you shoot a round like this, you start expectations running through your head and so forth, and that's the one thing that I'll have to try to suppress and hold off," Mickelson said Thursday evening. "We'll have three more rounds."

Following Mickelson on the odds sheet are Rory McIlroy and Martin Kaymer at 12/1. Kaymer enters the second round three shots back, while McIlroy trails by six.

Next up are Patrick Reed and Henrik Stenson at 15/1. Then it falls to 20/1 (Jordan Spieth, Dustin Johnson, Justin Rose, and Adam Scott).

Pre-tournament favorite Jason Day dropped all the way to 30/1 from 7/1 after an opening 73.

RELATED: The best part of Phil's 63? His caddie's reaction.


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