Wyndham Clark posted his only three birdies on the last three holes in the final round of the BMW Championship to rally from a poor start and win the playoff event on Sunday in St Louis.Clark, whose five-stroke lead vanished early on the back nine, shot an even-par 70 to put him at 17-under 263. That was good enough for a three-stroke victory over Patrick Cantlay at Bellerive Country Club, where the second stop in the FedEx Cup playoffs was contested.Clark’s only birdies of the day came when he rolled in a 16½ft putt on the par-3 16th hole to regain the lead and followed that with a 13-footer on the next hole. He sank a 17-foot putt to cap the triumph.Northern Ireland’s Rory McIlroy had tied Clark, but he took a bogey on No 17 in what amounted to a two-stroke swing among the golfers in the final pairing. McIlroy had 69 to finish at 13 under, sole in third.Cantlay’s 68 left him at 14 under.Clark, who won the US Open this year after another large lead shrank rapidly in the final round, rose to No 3 in the FedEx Cup standings. He’s behind only Scottie Scheffler and England’s Matt Fitzpatrick.Clark’s lead dipped to two strokes on Cantlay and McIlroy by the time the leaders reached the halfway mark of the final round. Then Cantlay birdied No 10 to tighten the top of the leaderboard.While Cantlay found the water at No 11 and went on to make double bogey, Clark’s bogey at No 10 allowed McIlroy to come within one stroke. McIlroy rolled in a 9-foot birdie putt on No 11 to pull even, giving him three birdies in a four-hole stretch.Clark actually led by six strokes late on Saturday before a bogey on the final hole. He began Sunday’s round with a bogey.Collin Morikawa shot 68, aided by an eagle on the 17th hole, to jump up to a tie for fourth place with Gary Woodland (69) and Chris Gotterup (69).Scotland’s Robert MacIntyre posted a 65 to tie Jake Knapp for the best round of the day. That left MacIntyre at 10 under and tied Maverick McNealy (68) for seventh place, catapulting him from outside the top 30 into the field for the Tour Championship next week in Atlanta.Despite a 66 for his best round of the tournament, JT Poston tied for 22nd place at 5 under, leaving him just outside of the top 30.Kurt Kitayama (68) tied for 26th at 4 under and was the first man out of the top 30, dropping from No 28. Field Level Media