Garcia, who in recent years took time off from golf in hopes of regaining his enthusiasm for the game and who has said he is perhaps not good enough to capture a major championship, was tied for the top with Marc Leishman after they both shot a 6-under 66 at the Augusta National Golf Club.
On a day in which 32 players broke par, an international cast of characters lined up to make a run at the year's first major crown.
World No. 1 Tiger Woods shot a 2-under 70 and said he was satisfied with the result. Nevertheless, he failed to take full advantage of the benign conditions and there were a dozen players in front of him including three former Masters winners.
Leishman, who captured his first PGA Tour event last year, birdied five holes on the back nine early in the day to take the lead. Garcia then got off to a hot start in the afternoon with three birdies in his first six holes and put together a bogey-free round to earn a share of the top spot.
Garcia, 33, entered the sport as a young sensation when he turned pro in 1999. Eight of his 23 worldwide victories have come in the United States, including The Players Championship, but he is still looking for a win that would serve as the signature achievement of his career.
Alone in third at 67 was Dustin Johnson, who has had two near misses in major events, and the crowd at 68 included David Lynn, Gonzalo Fernandez-Castano, Matt Kuchar, Rickie Fowler and former Masters champions Trevor Immelman and Fred Couples.
Fowler shot his 68 despite suffering double bogeys on both the first and 10th holes. Couples, at age 53, would be golf's oldest major champion by 5 years if he could pull off a win this week.
Zach Johnson, another Masters winner, shared 10th place at 69 with Jim Furyk and Adam Scott. Among those tied with Woods at 70 were David Toms, Lee Westwood, Justin Rose, K.J. Choi and Brandt Snedeker.
Rory McIlroy, who came into the tournament with high hopes after challenging at last week's tour stop in San Antonio, posted an even-par 72 that included four bogeys on the back nine.
Guan Tianliang, invited to the Masters at age 14 after he won the Asian Amateur title, shot a 73.
The first round was played in ideal golfing weather with little wind and only an occasional raindrop instead of the thunderstorms that had been forecast.
Heavy rains were expected to fall overnight, however, and the early starters were likely to find a soft golf course when they begin their second round on Friday.
Among the day's highlights was an ace recorded at the par-3 sixth by Jamie Donaldson. He went on to fire a 74.
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