$ 0 0 Tournament host Tiger Woods was denied a sixth win of the year in sensational fashion when he lost the Northwestern Mutual World Challenge in a playoff with Zach Johnson at Sherwood Country Club on Sunday.Johnson, who had twice finished second to fellow American Woods at this elite limited-field event, sealed victory with a rock-solid par at the 18th, the first extra hole, where Woods lipped out with a five-footer to bogey. The duo had finished regulation amid high drama and sharp swings of fortune on 13-under 275, Woods parring the last for a two-under 70 and Johnson, who came from four strokes behind with four birdies in the last eight holes, closing with a 68. Tied for the lead at 13 under, Johnson appeared to have the title firmly in his grasp in regulation when five-time champion Woods, from the left rough at the 18th, dumped his approach into a greenside bunker. However Johnson, perfectly positioned in the fairway, stunningly found water with his second, took a penalty drop and then holed out from 65 yards in the fairway for a par four as the galleries erupted in deafening celebration."It was just a bad swing and I got caught up in the moment,"Johnson said of his poor second shot from the 18th fairway. "Certainly the next shot was a little too dramatic for me, but I was very lucky to hit that one in." Woods did well to get up and down from the bunker to take the tournament into a playoff, but was unable to repeat the feat from a similar position in the same bunker on the first extra hole. Bubba Watson, the 2012 Masters champion, closed with a 70 to share third place at nine under with fellow American Matt Kuchar, who piled up eight birdies, a bogey and a double in a 67. Defending champion Graeme McDowell of Northern Ireland, who also triumphed here in 2010, signed off with a 69 to finish alone in sixth at five under.