Jordan Spieth has admitted that it is "really tough" to accept that he failed to defend his Masters title in Augusta.

The 22-year-old appeared to be on course for back-to-back triumphs when he rattled off four straight birdies to conclude the front nine.

However, that was immediately followed by six dropped shots in three holes, which eventually handed the green jacket to England's Danny Willett.

"It's really tough. That ball flight is one that's come up quite a bit for me, and I just put a bad swing on it," said the American.

"It was just a lack of discipline to hit it over that bunker coming off two bogeys. I went away from the gameplan I was using on the front nine and got a little conservative. It was a very tough 30 minutes that hopefully I never experience again."

Spieth had been bidding to become the youngest player in the tournament's history to record two victories.