(Reuters) - Top seed Dustin Johnson continued his "good mojo" to earn a tie for the first-round lead with Kevin Chappell and Hideki Matsuyama at the Tour Championship in Atlanta on Thursday. "I felt like I had good mojo going all day and swung it very nicely," Johnson told Golf Channel. Day continued to feel occasional twinges of the back pain that forced him to pull out of the previous playoff event, the BMW Championship, after three rounds. More...