His round started with a bogey at the first hole, but was followed by six birdies, including three in a row (4-6).
The first round featured a stinging criticism of the Gleneagles golf course by the tour's former top-ranked player, Lee Westwood of England.
"You can't bring the Ryder Cup onto greens like this," Westwood told the Scotsman newspaper after an opening 1-under 72.
The Ryder Cup competition against the United States will be held in 2014.
Scotland's Marc Warren, the defending champion, opened with an even-par 73, good for a tie for 23rd place with 16 others.
In 2007, Warren beat England's Simon Wakefield in a two-hole playoff.