PGA Tour: Spieth shoots 79, trails leader Villegas by 16

PGA Tour Player of the Year Jordan Spieth had a tough first round at the Northern Trust Open on Thursday, shooting an eight-over 79 at the Riviera Country Club in Pacific Palisades, Calif. When Spieth finished, he was tied for last in a 144-player field, 16 strokes behind leader Camilo Villegas.

Spieth's round included eight bogeys and a double bogey on 18. He struggled on the greens, taking 36 putts.

"This poa annua putts differently than it did last week at the courses that we played there in Pebble Beach, and so you've got to really be careful here. It can get away from you very quickly," Spieth said. "And it's hard to get below the hole. That's the thing out here."

Villegas shot an eight-under 63 at Riviera, making him the 18-hole leader by three strokes. He had a string of four consecutive birdies on the front nine.

Bubba Watson, who won the event in 2014, shot a five-under 66, putting him tied for second and three shots off the lead with Chez Reavie and Luke List.

Rory McIlroy, playing in his first PGA Tour event of the year, shot a four-under 67. He is tied for fifth, four shots off the lead along with Ricky Barnes, Charles Howell III and amateur Charlie Danielson, among others.