McIlroy takes tumble down leaderboard with 2 water balls, on back 9 at Augusta National

Rory McIlroy, of Northern Ireland, chips to the second green during the third round of the Masters golf tournament Saturday, April 13, 2013, in Augusta, Ga. (AP Photo/David J. Phillip) (The Associated Press)

Rory McIlroy has tumbled down the leaderboard after dropping five shots in five holes at the Masters.

He put two balls in the water on the back nine, and was in such a slump he needed pars on his last two holes just to break 80 on Saturday.

At 5-over for the tournament, he trails the leaders by double digits.

The No. 2 player in the world called it a "very frustrating day," and says his chances to win at Augusta were "gone" after the five-shot swing. He dropped three more shots when he went in the water on 15 and made bogey on the par-3 16.

The 79 was McIlroy's second-worst score in 17 rounds at Augusta National. The only time he's shot worse was in 2011, when he blew the tournament lead on the back nine on Sunday.