The round, which was kickstarted by a 35-footer for eagle at the par-5 seventh hole, was the byproduct of a session with swing coach Peter Kostis last week and drastically improved play off the tee.
“My grip had become too weak and my ball position had crept forward,” said Casey, who hit 13 of 14 fairways on his way to an opening 66. “He knew straight away what to do to fix it.”
Casey had struggled following an assortment of injuries in recent years, but he rebounded last year with his victory at the Irish Open on the European Tour and has five top-25 finishes on the PGA Tour this season.
“There was an epiphany moment at the end of 2012, maybe at the BMW Masters in China, where I could tell I hit it well and the ball was going where I wanted it to,” said Casey, who also plans to play Monday’s qualifier for the U.S. Open.