After an hour-long frost delay at chilly TPC Scottsdale, Fowler played the first six holes in 5 under.
Lowry birdied seven of his first 13 holes, then bogeyed the next two. Matsuyama was in one of the last groups to finish before play was stopped because of darkness.
Anirban Lahiri was a stroke back at 66, and Bryce Molder also was 5 under with two holes left when play was suspended.
Phil Mickelson settled for a 69 after dropping four strokes in a two-hole stretch. On his back nine, Mickelson bogeyed the par-3 fourth and followed with a triple bogey on the par-4 fifth.
