Day has been sidelined since the WGC-Accenture Match Play Championship with an injured left thumb but a cortisone injection at the end of March has put the Australian on the right track.
Having finished in the top three in two of the past three tournaments at Augusta National, Day's declaration that his thumb is 'fine' will see the 26-year-old ranked among the favourites to win the green jacket.
"It's fine," Day said on Monday.
"There's no pain. I'm taping it just as a precaution. To be able to swing pain-free now is great... I've played 36 holes here over the last four days, and the hand's coming up nicely.
"I'm really looking forward to a nice, solid start."
Day last competed in a stroke-play event was the AT&T Pebble Beach National Pro-Am at the start of February, where he finished in a tie for 64th.
But in his previous two events on the PGA Tour this season, the Queenslander had finished in a share of ninth at the Northwestern Mutual World Challenge for ninth and tied for second at the Famers Insurance Open.
"The injury was more frustrating for me because...I was playing some pretty good golf," Day said.
"It was trending in the right direction going into the Florida swing there."
Day led by a stroke halfway through last year's Masters and was two shots off the lead with a round to play before his compatriot Adam Scott went on to become the first Australian to claim a green jacket.
In the end, Day finished two shots behind Scott and Argentina's Angel Cabrera, who lost the play-off.
Day hopes he can match Scott's achievement this year.
"I always wanted to be the first Australian to win it... but I'm happy to be the second," the world number four said.