Tiger Woods has clung on to his world No.1 ranking despite finishing joint second-last in the WGC Bridgestone Invitational tournament, won by Hunter Mahan.Woods ended a disastrous week with a final round five-over-par 77 to finish 78th in the 80-man field -- a remarkable 30 strokes off the leader -- his worse-ever performance in professional golf.However, despite Woods' implosion in Ohio, nearest challenger for the top spot, Phil Mickelson, failed to capitalize.The left-hander -- who needed to finish in the top four to overtake Woods -- actually fared worse than his rival on Sunday, posting a round of 78 that left him tied in 46th position.There were no such dramas for Mahan though, who hit five birdies on the front nine on his way to a blemish-free six-under-par 66.That gave him a 72-hole total of 268 (-12) for a two-stroke victory over fellow-American Ryan Palmer (69), with Retief Goosen and Bo Van Pelt another shot adrift in equal third.It was Mahan's second PGA Tour victory of the season, following his Pheonix Open triumph, and the third win of his career.The win also sealed Mahan's Ryder Cup place, moving him up to second in the standings with just one more qualifying event to come.Mahan's qualification for Celtic Manor will give him his fourth successive Ryder Cup appearance -- although the other three were always as a "captain's pick"."That was my goal at the beginning of the year, to make the Ryder Cup team on my own," Mahan told the official PGA Tour website.Source: CNN