(CNN) -- Golf is a sport where concentration and the ability to perform under pressure is key. So how was Webb Simpson feeling during Sunday's final round of the U.S. Open, knowing he was within touching distance of winning his first major title?
"I couldn't really feel my hands or my legs," the 26-year-old told CNN after carding 68 in each of the two final rounds to finish one over par at San Francisco's Olympic Club.
"My legs felt like they were a couple of hundred pounds each ... It was very nerve-wracking."
But the new world No. 5 put together a run of four birdies in six holes in the middle of his final round to move above overnight leaders Graeme McDowell, who missed a 25-foot putt at the 18th to force a playoff, and fellow American Jim Furyk.
"I'm pretty excited, I'm pretty worn out," he said, after clinching the third PGA Tour title of his four-year career and taking home the $1.44 million first prize.
"It's such a long week, such a grueling week on your mind, and this place is hard to walk. So physically it's a tough week as well.
"But I couldn't have imagined I'd be U.S. Open champion this early in my career. I didn't expect that it would come this quickly. One thing I've always done is I've never put limits on what can happen with this game."
The North Carolina native, who tied for 14th at Congressional last year in his only previous U.S. Open appearance, is hoping to capitalize on the run of form which has propelled him to one of golf's four biggest prizes.
"You can get on runs out here, you wins and your good play comes in bunches. I want to take advantage of that. One thing I pride myself in is remembering how I got here and remembering what makes me tick as a golfer," he said.
"So win or lose I'm trying to get better, and that's what I've been trying to do for the last couple of years."
Simpson said the continued shouts from the crowds gathered on the Lake Course kept him guessing on a foggy day in California.
"This week I felt like they were especially great. I looked at my caddy on 14 and asked him, 'Are the crowds are lot louder today?' because it seemed like we were hearing roars every few minutes," he said.
"It was so fun to play in an atmosphere like that. The famous 18th hole, coming down the hill and going back up to the clubhouse, is probably the coolest finish I can imagine in golf."
Despite becoming the third consecutive American winner of a major -- following on from Bubba Watson at the Masters and Keegan Bradley at the PGA Championship -- and the 15th different major winner in a row, Simpson's participation at next month's British Open is in doubt.
He and his wife Dowd are awaiting the birth of their second child, and Simpson is looking forward to sharing his tale of Father's Day glory with his children in the years to come.
"I got to talk to my dad and I told him, 'Happy Father's Day,' and he said it was a pretty good Father's Day present for him. It's a fun memory that I can't wait to share with my son one day."