Augusta, GA (SportsNetwork.com) - Jordan Spieth mixed four birdies and three bogeys over his first 12 holes on Sunday, and leads the Masters by four strokes with six holes to play.

Spieth was 17-under par for the tournament. The 21-year-old is in search of his first major championship title.

Three-time Masters champion Phil Mickelson was 2-under through 13 holes and had climbed into second place at minus-13.

Justin Rose, the 2013 U.S. Open winner, is alone in third place at 12-under par.

World No. 1 Rory McIlroy, Dustin Johnson and Hideki Matsuyama share fourth at 10-under.

Four-time winner Tiger Woods injured his right arm on the ninth and is even- par in the five holes since. He was 1-over for the day and 5-under for the tournament.

Spieth had two birdies and a bogey in the first six holes. Between bogeys at seven and 12, Spieth birdied the eighth and 10th.

Rose missed a 5-footer on No. 7 that would have gotten him within two. He has four pars and a bogey since to dip back to minus-12.

Mickelson played the front nine in even-par with two birdies and two bogeys. He has birdied the 10th and 13th to move into second place at minus-13.

Hunter Mahan carded a 5-under 67 and is finished at 8-under-par 280. Rickie Fowler (67), Ryan Moore (69) and Bill Haas (70) are in a minus-6.

Last year's winner Bubba Watson struggled to a 2-over 74 and finished his title defense at 1-over-par 289. Watson ended in a tie for 38th.