Rory McIlroy finished with the lowest four-round score of all time at the U.S. Open five years ago when he shot a 16-under 268 at Congressional Country Club. Jason Day finished second that year, eight strokes behind McIlroy.
Day and McIlroy opened as 7-1 co-favorites to win the U.S. Open this week at Oakmont Country Club at sportsbooks monitored by Odds Shark, though oddsmakers have since given Day a 13-2 edge and bumped McIlroy's odds of winning back to 15-2.
Defending U.S. Open champion Jordan Spieth shot a five-under 275 a year ago at Chambers Bay to edge Dustin Johnson and Louis Oosthuizen by one stroke.