Rory McIlroy's Waste Management Phoenix Open challenge looked to be all-but over before it even began as the former world number one found himself on three over after just two holes.
The Holywood native began with a double-bogey on his opening hole, the tenth, before adding another bogey on the next.
However, the four-time major winner bounced back with three birdies on the 13th, 15th and 16th holes to turn on level par, and McIlroy then moved to two under with back-to-back birdies on the second and third holes.
McIlroy handed a shot back on his penultimate hole to move into the second round on one under par, tied for 52nd at the Arizona event.
Padraig Harrington was also in action in Phoenix where Mark Hubbard and Matthew NeSmith share the lead.
Harrington posted a flawless front nine, turning on two under par and added a third birdie on the 15th hole to move to three under with three to play.
However, the Ryder Cup captain finished as McIlroy began, dropping three shots in the final two holes to end his round on level par.
The three-time major champion handed one shot back on the 17th before making double bogey on the last to share 70th place.
The American duo atop the leaderboard both shot eight-under 63s, while compatriots Nate Lashley and Sam Burns are a shot further back on seven under par.
Steve Stricker rolled back the years to sit in fifth spot on six under, while Xander Schauffele is in a group sharing sixth place on five under par.