Spieth, the defending champion, was comfortably in first until the 12th hole, when he hit the ball into the water twice and finished with a quadruple-bogey.
Willett hits off the 12th tee on Sunday. He had five birdies and no bogeys in the final round.
Smylie Kaufman hits from the first fairway during the final round. Kaufman, playing in the Masters for the first time in his career, started the day in second place.
Jamie Donaldson climbs out of a bunker on the fourth hole Sunday.
Rory McIlroy reacts to a bunker shot on the second hole Sunday.
Spieth hits a tee shot during the third round on Saturday, April 9. Spieth shot a 1-over 73 to lead the tournament for a third straight day.