US Open champion Dustin Johnson birdied four of the final five holes to open up a three-shot lead over Paul Casey after the third round at the BMW Championship in Indiana Saturday. Johnson delighted fans with another display of long hitting but also displayed a deft touch on slow greens at Crooked Stick in Carmel. He carded a 68 to post an 18-under-par 198 total, while Englishman Casey also shot 68 to lurk in second place at 15-under, with American J.B. Holmes (68) another shot back. Johnson has plundered the par-fives, playing them in 11-under, and his length has become an even more valuable weapon on a course softened all week by heavy rain. "With all the rain we got last night I struggled with the speed (on the greens) early in the round, kept leaving everything a little bit short but got a handle on it the back nine and finished off really nicely," the world No. 2 told Golf Channel. "I'm seeing the lines really well. The putter is working. It's just going where I'm looking. I feel like I read the greens very well. I'm making some putts this week." Johnson, using a putter he put in the bag this week, launched his finishing flourish with a 10-foot birdie at the 14th. He had a tap-in birdie at the par-five 15th and then made it a hat trick at the 16th, before capping off his day with a 15-foot birdie at the last. Despite the cushion, Johnson can take nothing for granted. He has converted only two of his previous six 54-hole leads on the PGA Tour into victory. "I'm not going to change anything," he said. "I feel I've got a good game plan out here, be aggressive on flags when I feel like I've got a good club and a good number and other times there are a few holes you just want to make par on and keep going." Casey is in contention for the second consecutive week. He led going into the final round at the Deutsche Bank Classic, before finishing runner-up to Rory McIlroy. The BMW Championship is the third of four FedEx Cup playoff events on tour. The top 30 players on a points list on Sunday advance to next week's Tour Championship in Atlanta. Lee retains crown In Cheonan, defending champion Lee Kyoung-hoon fired a final-round 68 to win the Korea Open title for the second time Sunday. He carded 16-under-par 268 for a three-stroke victory over countryman Choi Jin-Ho at Woo Jeong Hills Country Club in Cheonan. Choi mounted a strong challenge on the front nine before three straight bogeys from the 10th derailed his glory bid. One shot behind was Kang Kyung-nam, who was looking to re-ignite his career after completing his mandatory military service last year. Choi, two strokes behind after the third round, drew level with Lee after birdies at the first and the fourth, turning the contest into an engrossing duel. Lee shot four straight birdies from the par-five fifth hole as Choi picked up three shots in the same stretch. But Choi's challenge crumbled after the turn with three bogeys on the trot. Thailand's Namchok Tantipokhakul shot a 69 to finish as the highest-placed overseas challenger in equal 12th spot, 11 shots behind Lee. — Agencies
