Day, who lives in nearby Columbus and is a member at host Muirfield Village, fired a four-under-par 68 to sit just three shots back of a mixed bag of leaders on day one at the Jack Nicklaus-hosted event.

Japanese World No.10 Hideki Matsuyama added some star power when he shot a 65 in soft conditions to join former amateur World No.1 Joaquin Niemann from Chile and Mexican golfer Abraham Ancer atop the leaderboard at seven under.

The trio are one ahead of American Beau Hossler (66), while Kyle Stanley, Grayson Murray and Jamie Lovemark all shot 67s to sit at five under.

Day, whose poor record at Memorial includes just one top-25 from nine appearances, jumped out the gates with a birdie on the 1st hole before adding three more on the front side and another at the par-4 10th.

But a costly bogey at the par-3 12th crippled Day's momentum.

Day misses a birdie putt on the 17th hole during the first round of The Memorial Tournament. PHOTO: Sam Greenwood/Getty Images.

The former World No.1 is five shots better than fellow Australians Adam Scott and Cameron Davis who along with Tiger Woods (72) sit at even par.

Five-time Memorial champion Woods delighted the Muirfield Village galleries when he rallied back from a nightmare score which blew out to four over during his front nine, which he attributed to back soreness.

"My back is fused; I'm going to have days where it's just tight," Woods said.

"I didn't feel my swing and consequently I hit it both ways but I fought back."

Rod Pampling (73) Marc Leishman (74) and Cameron Smith (75) round out the Australian contingent.

Evin Priest, Australian Associated Press