The six-shot lead at the midway point tied the U.S. Open record first set by Tiger Woods at Pebble Beach in 2000 and matched by Rory McIlroy at Congressional three years ago. Woods wound up winning by 15 shots. McIlroy won by eight.
Phil Mickelson steadied his putting stroke a bit but still shot 72, not the sort of score he needed to get in contention for his first U.S. Open title.
Lefty has been the runner-up in this championship a record six times, denying him the only title he needs to complete a career Grand Slam.
Defending champion Justin Rose, who held off Mickelson a year ago at Merion, shot 70 but was still 10 shots back as he headed to the clubhouse.
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