Flores, a 35-year-old American ranked 299th in the world, fired his second consecutive six-under par 66 to seize the second-round lead at 12-under 132 in the US PGA Tour event at Glen Abbey in Oakville, Ontario.
“I was putting the ball in the fairway, that’s for sure,” Flores said. “I kept getting the ball up and down, kept the momentum going in my favor.”
Flores, who began his bogey-free round on the back nine, birdied the par-3 12th, then closed his opening nine with birdies at the par-5 16th, par-4 17th and par-5 18th. He added a 20-foot eagle putt at the par-5 second to claim a one-stroke lead after 36 holes.
Americans Woodland, Brandon Hagy and Matt Every shared second on 133, one stroke ahead of Singh, Australian teen Ryan Ruffels and Americans Kevin Chappell, Charley Hoffman and Harold Varner.
Fiji’s Singh, 54, skipped the Senior British Open in Wales to play in Canada, where the 50-and-over Champions Tour standout could become the oldest US PGA Tour winner in history, eclipsing the feat of Sam Snead when he won at Greensboro in 1965 at age 52.
World Golf Hall of Famer Singh, a three-time major champion, has 34 career wins but has not won a US PGA event since taking the 2008 Deutsche Bank Championship on his way to the season money crown.
“Champions Tour is way different than this,” Singh said. “To come over here and play, you’ve got to bring it. You’ve got to get your game out there and play hard.”
Singh, another back-nine starter, had three birdies in his first nine holes, then opened with birdies on the first and second holes, the first on a 32-foot putt. After a bogey at the third, Singh sank a 22-foot birdie putt at the par-4 fifth but stumbled with a bogey at the par-3 seventh.
Woodland threatened the course-record of 62, shot four times, most recently by Aussie Greg Norman in 1986. But he settled for his US PGA career-low round with a 63.
Woodland opened on the 10th holes as well and after two birdies in four holes suffered his lone bogey at 14.
But Woodland followed with six birdies in a row, the most impressive of them being a 26-foot chip from a bunker at the 18th.
“I was trying to just keep it going,” said Woodland. “Holing the bunker shot was huge. I drove the ball in play and gave myself a lot of chances.”
A tap-in birdie at the par-3 fourth and 12-foot birdie at the par-3 seventh put him on the brink of the mark, but a 13-foot birdie miss at 18 ended his bid for a 62.
“I had everything clicking,” Woodland said. “It has been coming together for a while. I just hadn’t done it. I was driving it well and the putts were going in.”
Woodland has two runner-up finishes this season, at the Honda Classic and Mayakoba Classic in Mexico, as he chases a third PGA title after the 2011 Transitions Championship and 2013 Reno-Tahoe Open.