By Larry King TROON, Scotland (Reuters) - Phil Mickelson grabbed a piece of golf history at the British Open on Thursday, capturing a share of the record for the lowest score in a major championship -- and coming within fractions of an inch of taking the record outright. Aided by birdies on 10, 14, 16 and 17 on Royal Troon's dangerous back nine, Mickelson posted a final score of 63, equaling the record low for majors.