Atlanta, September 26 Swede Henrik Stenson held firm at rain-soaked East Lake Golf Club, while Jordan Spieth made a charge to stand three strokes back after Friday’s second round at the season-ending Tour Championship. Stenson, who won the event wire-to-wire in 2013, made it six rounds in a row holding the lead at Bobby Jones’ old stomping grounds near downtown Atlanta as he built on his two-shot overnight lead with a two-under 68 for a nine-under 131 total. “So, a two-shot lead yesterday and a three-shot lead now after two rounds. Whenever you can maintain it or extend it is always a good thing,” said Stenson.Masters and US Open winner Spieth posted a bogey-free 66, the low round of the day, firmly rolling in a 20-foot birdie putt at the last to reach six-under 134. Englishman Paul Casey bogeyed the last for a 70 to slip back to five under par, where he began the day in second place. Spieth began to lock in the speed of the greens, needing only 23 putts as he rescued a number of pars with some brilliant up-and-downs with his vaunted short game. Another stroke back was British Open champion Zach Johnson, who lost five shots to par in five holes from the ninth but recovered with three birdies in the last four holes for a level-par 70 that put him at four-under 136. Rory McIlroy (71) and Australian Steven Bowditch (69) stood six strokes behind Stenson at three-under, while world No 1 Jason Day shot 71 for level-par 140. More than an inch and a half of rain fell overnight and light rain continued for most of the day, cutting down fairway roll, muddying balls, making the tricky rough harder to escape and playing havoc with reading the speed of the greens. Sixteen players posted under-par rounds on Thursday, while only four managed to dip under 70 in the second round. Double bogeys stalled the charges of several players including Casey at the par-three sixth, Johnson at the par-five ninth and Rickie Fowler (70 for 139) at the par-four 13th. Even Stenson, who has ruled East Lake in his two appearances, stumbled.