J.T. Poston used a burst of birdies to build a comfortable lead in the morning and afternoon, first for a three-shot lead after 54 holes and then to give himself a big enough cushion to hold on for a 4-under 67 and a one-shot victory Sunday in the Shriners Children’s Open. Poston never trailed since making a 20-foot birdie putt on the 14th hole when he returned to finish the third round. Poston still had to sweat it out to the very last putt.