IRVING, Texas — The weather-delayed first round of the Byron Nelson Championship has ended with seven players tied for the lead at 4-under 66.

Blake Adams birdied two holes and Michael Sim had one birdie to move into a share of the top spot Friday.

Hunter Mahan, Jarrod Lyle and Steve Elkington were tied overnight, and finished their rounds where they began. Jason Day and Joe Durant were the other leaders. They finished their rounds Thursday.

Honolulu's Parker McLachlin was one stroke back after an opening round 67.

U.S. Junior Amateur champion Jordan Spieth — a 16-year-old high school junior from Dallas — finished his first round with two birdies for a 68 in his PGA Tour debut. He is two strokes off the lead.

The second round started Friday, and Elkington opened with three birdies in four holes to reach 7 under.