He carded a four-under final round of 68 to finish on 18 under par, two shots ahead of fellow Englishman Matt Wallace and Patrick Reed of the United States.

The 31-year-old nearly hit his tee shot into a stream on the 18th hole before recovering to make par.

"I'm massively proud of myself," an emotional Willett told Sky Sports.

"It's been a lot of hard work. It's been tough [the past two years]."

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Willett won his first major at Augusta two years ago but slipped from a career-high of ninth in the rankings to outside the top 450 earlier this year because of injury and a loss of form.

He shared the lead with Reed going into the final round, but went three shots clear with an eagle on the par-five second and then made birdie on the seventh.

He lost that lead after bogeying the 10th and 12th, but birdied three more holes before holding his nerve on the 18th.

"You never quite know when a win is around the corner. With everything that's happened you're never sure if another win is going to come," Willett said.

"It's been a hell of a lot of work. It's just nice to be back.

"I've started pretty slowly on the first four or five holes all week - but I got off to a quick one today. For that to happen on a Sunday in the position I was in, I knew I was in a good place."