FORT SMITH, Ark. -- Colt Knost hopes he can put the questions to rest. When Knost turned pro last fall, he turned down invitations to this year's Masters, U.S. Open and British Opens and caught a lot of flak from the skeptics about his decision to leave the amateur ranks.

The reigning U.S. Amateur champion fired a 5-under-par 65 Sunday and erased a six-stroke deficit to win the Fort Smith Classic, his first victory as a professional.

Knost bogeyed his final hole at Hardscrabble County Club to finish at 12-under-par 268 and then had to wait more than an hour to see if anyone would catch or pass him. Darron Stiles, who was in the last twosome, was the leading candidate to challenge Knost.

Stiles rolled in an 18-foot birdie at No. 16 to temporarily tie for the lead, but the 2006 tournament champion then bogeyed No. 17 to fall one back. Stiles' 9-iron from the middle of the fairway wound up 35 feet from the pin and when he missed his birdie attempt, the title and the $99,000 first-place check belonged to Knost.

"The questions just kept going and going. It seems I answered the same thing over and over," said Knost, whose 65 was three strokes better than anyone else in the field. "After a while, it got really frustrating. People looked at it as the Masters, but that's just one tournament. Golf is not one tournament. I'm trying to make a future out of this game."

The future for the 22-year-old is indeed bright after his charge during the windswept closing round.

"I thought I blew it yesterday. I played the last four holes in 4 over par and I thought that did me in," said Knost of his third-round 70 that included a trio of three-putt bogeys on the back nine.

"When I saw the wind was blowing so hard this morning, I thought maybe I'd have a chance," he added. "I thought if I could shoot 5 or 6 under, you never know what could happen. I'm from Texas and I like playing in the wind."

Knost started the day six back of 54-hole leader Matt Weibring (75-272) and moved up the leaderboard courtesy of an old, new putter. Last week, the former SMU Mustang ditched the belly putter he'd been using and went back to a regular-size one he's had for several years.

"I putted unbelievably well today," said Knost, who needed only 23 putts on the last day. "That's been the difference for me all year. I just haven't putted well, but this week it finally came together. I rolled it really well today."

While Knost was moving forward, the course was playing more than 2 1/2 strokes above par and putting the rest of the field in full reverse. When Stiles rolled in a 35-foot birdie putt at No. 9 to get to 14 under, his lead was three strokes over Weibring. Knost was four back before he made a final push with birdies at Nos. 14, 16 and 17.

"It was brutal out there," said Knost, who moved to No. 7 on the money list. "I definitely tried to play aggressively when I could, but I figured if I could give myself some 15- to 20-footers, I'd have a chance to make some birdies. Mostly, I just tried to keep out of trouble."

Trouble found Stiles at Nos. 13 and 14 when a pair of 3-wood tee shots put him in trouble and resulted in a bogey and a double bogey. The latter coming about the time Knost was finishing his round and dropped him back to 11 under and one behind.

"The whole back nine was Jekyll and Hyde for me," said Stiles, who was in a similar position two years ago and ultimately needed a playoff to win. "I just didn't execute on a couple of shots when I needed to."

Despite the runner-up finish, Stiles' payday of $59,400 pushed him over the $200,000 mark and moved him from No. 6 to No. 1 on the money list. The top 25 players at the end of the year will earn PGA TOUR cards for 2009.

"I feel like the Nationwide Tour is the perfect place for me right now," said Knost. "I'm learning how to play and hopefully it will get me to the PGA TOUR and maybe I'll get to play in the Masters then."

Final-Round Notes: Lift, clean and place conditions were in effect all four rounds. ... The final-round scoring average was 72.607 and pushed the four-round total to 70.301. ... The Nationwide Tour moves to Greenville, S.C., next week for the BMW Charity Pro-Am, which will be contested at three different courses.

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