Crane took advantage of a 3½-hour delay that left nearly perfect scoring conditions with no wind and rain-softened greens. He had five of his seven birdies on his final nine.
Crane needed only 24 putts for his best round of the season, including a 27-footer for birdie on his final hole at No. 9 with only a handful of people watching because officials closed the course to spectators because of the high winds with the storm.
Sixty players were unable to finish the round.
Peter Malnati shot 65, and Billy Horschel also was 5-under with two holes left to play.
Retief Goosen and Joe Durant each had 66, and Phil Mickelson opened with 67.
Mickelson came here hoping to get sharp for next week’s U.S. Open at Pinehurst No. 2, and he did just that.
He hadn’t shot below 70 since the third round of the Wells Fargo Championship. He missed the cut at The Players Championship and tied for 49th last week in the Memorial Tournament.
Lefty hasn’t won in 19 events dating to the British Open.
“I did exactly what I need to do and some momentum that I need heading into the U.S. Open,” Mickelson said. “Tomorrow’s round, the same thing. Finish strong and play a good round.”
Finishing with the three birdies in his final four holes was exactly what he wanted in a round with five birdies and two bogeys.
He hit his approach from 135 yards on the par-4 sixth to 5 feet and rolled in the birdie putt. He left himself longer putts with a 7-footer on the par-3 eighth and an 11-footer on the par-4 ninth, but knocked them in for his strong finish.
“I’ve been struggling with finishing the round strong,” Mickelson said. “I had a good round last week on Thursday and then played poorly. To birdie three of the last four made it a great round.”