Daniel Chopra carded a 4-under 66 to join Rick Price in a tie for third.
Singh played the back nine first at The Links of GlenEagles and collected three birdies over his first nine holes.
The 31-year-old from India added a birdie at the second and another at the fifth to move to minus-5. Singh soon found trouble, however, with back-to-back bogeys starting at the par-5 sixth.
Singh recovered well with birdies at eight and nine for his share of first under cold and windy conditions.
'My putting was unbelievable today,' said Singh. 'My ball striking was average but my putting was excellent.'
Standly also started at No. 10 and was on fire early with five birdies on his outward nine.
Standly then birdied the first to reach 6 under, but the 39-year-old found trouble with a bogey at the par-3 fifth.
'Everything really went good today,' said Standly. 'Everything flowed today. I had some good numbers coming into the greens. I had some good putts that I could be somewhat aggressive with.'
Joe Ogilvie, who leads the Nationwide Tour money list, tallied five birdies and two bogeys for a round of 67.
Ogilvie finished alongside Kevin Johnson, Tommy Tolles, Derek Gillespie, David Branshaw, Christian Pena, Jason Schultz, Scott Gutschewski, Scott Hend and Chris Wall in a tie for fifth.
'It was not a typical Tommy Tolles round,' said Tolles. 'Today, with it being a little breezy and not knowing the course all that well, even-par is not a bad score. I think as the days go by, players will get a little more adjusted to it and the scores will steadily come down.'
Tom Carter, who earned his first of two victories of 2003 at the Canadian PGA Championship earlier this year, and Michael Long highlight a group at 2-under-par 68.