Tommy Fleetwood will go into the final round of the RBC Canadian Open two shots off the lead after a third-round 67.
Fleetwood's three-under total for the day left him in a four-strong group on 11 under, one shot behind Bud Cauley and two off clubhouse leader Jackson Suber.
Suber signed for a 66 after a booming 348-yard drive set him up for a birdie at the par-five last and earned him the outright lead going into Sunday at a PGA Tour event for the first time.
Ben James, the pro debutant who ended Friday as the shock leader, came back to earth with a resounding bump as an eight-over 78 took him completely out of contention.
"I played very well. I think it was like a really solid day," Fleetwood said. "I was hitting really good shots and didn't really make the most of it, a few putts slid by.
"I felt like the finish was kind of tricky. The wind switched a little bit, felt like the holes weren't playing that easy. I hit two poor iron shots really, 16 and 17, and that was all - that was the only bit that was poor.
"I did a lot of good stuff and overall I think it was a good round."
Brooks Koepka - who shared the co-lead at six under after the opening round - had to deal with a mysterious feeling in his left arm that made it difficult for him to grip the club most of the day, leaving him two over by the close of play.
"I'm struggling to grip the club with my ring finger and pinkie finger, so can't grip it," Koepka said after salvaging a 72, leaving him seven shots behind. "My fingers would come loose, it was kind of numb. I don't know what the deal was but hopefully we'll figure it out."
He had treatment on the course and said he had never experienced anything like that.
Fleetwood, though, began the day two behind James and could scarcely have wished for a better start as he reached the green at the par-five first in two and holed a 16-footer for eagle.
That was as good as it got on the front nine, but a short approach at the 12th left him an eight-footer for a birdie, and another followed from five feet at the short 14th after a fine tee shot.
The only blemish came at the tough 17th, where Fleetwood's second found rough to the right of the green and he failed to get up and down in two from there.
Only three players birdied the 521-yard par-four all day, among them Billy Horschel, who did so with a putt from just shy of 99 feet on his way to a 64 and a total of 10 under.
Four others join him there, including Sam Burns, while Fleetwood's companions a shot further ahead are the Swede Jesper Svensson and American pair Brice Garnett and Wyndham Clark, whose seven-under 63 - featuring seven birdies and no bogeys - was the round of the day.
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