'I flinched': Mickelson lets an opportunity slide at Pebble

Phil Mickelson reacts after missing a putt on the ...

Phil Mickelson reacts after missing a putt on the ...

Phil Mickelson watches his tee shot on the second ...

Phil Mickelson watches his tee shot on the second ...

Phil Mickelson hits out of the bunker on the 10th ...

Phil Mickelson hits out of the bunker on the 10th ...

PEBBLE BEACH, Calif. (AP) — It was the kind of mistake that could cost a guy the U.S. Open.

"I flinched," Phil Mickelson said about a 12-inch putt that rimmed out on the third green Thursday.

It was hardly the worst thing that's happened to Mickelson at the major that has escaped him, %href_on(file: