Hadwin matches Scheffler for midway lead at PGA Phoenix Open
Hadwin, whose only PGA victory came at the 2017 Valspar Championship, was level with reigning Masters champion Scheffler on 10-under 132 after 36 holes at TPC Scottsdale.
After finding a bunker at the par-3 12th hole then sinking a 25-foot par putt, Hadwin charged back.
He left his third shot inches from the cup at the par-5 13th to set up a birdie and sank a birdie putt at 14 from just inside 10 feet on his way to a second straight five-under-par 66 round.
"This morning was nice," Hadwin said. "We had a little bit of breeze it seemed like for 15 or 20 minutes. But it really wasn't too crazy. Definitely settled down from yesterday. Hit some good shots.
"I would have liked to have made a couple more putts coming in. That's golf. Just keep plugging away."
Hadwin will tee off in the final group in the afternoon third round alongside second-ranked American Scheffler and Spain's third-ranked Jon Rahm - both of whom can overtake world number one Rory McIlroy with a victory.
"Overall obviously in a really good position. It's going to be a fun Saturday," Hadwin said. "Two of the best players in the game. So it's a big opportunity for me and one that I'm looking forward to."
Rahm shared third, two strokes off the pace on 134, with reigning Olympic champion Xander Schauffele and three-time major winner Jordan Spieth.
The tournament has been fighting to get back on schedule since a Thursday morning frost delay.
Defending champion Scheffler fired seven birdies in shooting 64 on Friday to seize the overall lead but half the field was unable to finish before darkness forced a Saturday finish to the second round.
McIlroy made four pars and a bogey on the 17th hole on Saturday morning to complete a second-round 67.
Scheffler won his first PGA crown last year at Phoenix to launch an incredible run that included victories at Bay Hill and the WGC Match Play as well as the Masters to reach world number one.
A hot 2023 start for former US Open champion Rahm with victories at the PGA Tournament of Champions and La Quinta, California, last month has the Spaniard poised to topple McIlroy as well.