Francesco Molinari said he was as surprised as anyone to win The Open Championship at Carnoustie.
The Italian posted a bogey-free two-under-par 69 to win on eight under, two clear of Justin Rose, Rory McIlroy, Kevin Kisner and Xander Schauffele.
"I knew I was coming in playing some good golf but my record round here was terrible," said the 35-year-old.
"So that didn't make me too optimistic. To go bogey-free in the last two rounds is unthinkable."
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Molinari, who on Sunday parred his first 13 holes before carding birdies on the 14th and 18th, is the first Italian to win one of the sport's four majors.
"It's just disbelief," he added. "Look at the names on the Claret Jug. It's the best golfers in history and to be on there, it's incredible.
"And for someone like me, coming from Italy, which is not a major golfing country, it's been an incredible journey."
He conceded he had not been able to watch Xander Schauffele play the final two holes. The American, who had been in a three-way tie for the lead after round three, was seven under and needed to birdie one of the last two holes to force a play-off.
However, he bogeyed the 17th and when his second to the 18th only found the green, Molinari, who will climb to world number six in the rankings, knew he had won - although he had to be told because he was on the practice putting green.
"I would have felt sick watching on television," he said. "That's why I went to the putting green. Big credit to my wife who watches me all the time. I don't know how she does it."
Taking on Tiger
Molinari, who started the final round three shots off the lead, was paired with three-time Open champion Tiger Woods and the American started well with birdies on the fourth and sixth holes to move one ahead of Molinari and top the leaderboard on seven under after nine holes.
The roars that followed Woods' birdies attracted ever-more fans to the group and by the ninth, dozens were half running down the side of the fairway to gain a good vantage point.
However, a double bogey on the 11th, after hitting a spectator with a wild second shot, and a bogey on the 12th checked Woods' challenge.
Molinari, who two-putted from 90 feet for par on the 12th, said: "Playing with Tiger was another challenge.
"I've played with him before in Ryder Cups and in big occasions. so I knew what was coming and I was ready for it.
"Obviously there's a lot more people if you're grouped with him but he was great, really good sportsmanship. He had it going on the front nine and then unfortunately he hit a couple of loose shots on the back nine. It's hard not to pay for missed shots at Carnoustie."
He has now won three of his last five tournaments and asked how he would celebrate added: "I don't know. I had a flight booked for 09:00 on Monday to get back home, so I think that's gone. I have a holiday plan with the family next week, hopefully we can still make that and relax for a few days."