David Duval is looking forward to the challenge of Shinnecock

The former world number one has not played a pro event since he withdrew from the Dunlop Phoenix in Japan in November because of a sore back.

He subsequently took time out to be with his family and work on his game.

"I came to play this week, but I can't tell you when I'm going to play again," the former Open champion said.

Duval was the last player in the 156-strong field to register for the second of the year's four majors.

"I didn't really know when I would play again," the former world number one told reporters at Shinnecock Hills Golf Club.

"I just felt like, at some point, I would feel I was ready to go, just play and have some fun.

"It just kind of hit me on Saturday night that I wanted to play - for no other reason than I thought I was ready.

"Up to that point, I hadn't wanted to play. And I hadn't missed being away, to be honest," he added.

"The US Open is a very hard thing for me to miss and I was anxious for my wife and my family to see me and see what I do, to see the atmosphere of tournament golf."

In 1998, Duval led the US money list with earnings of more than $2.5m.

One year later, he became the third player to shoot a magical 13-under-par 59 on the PGA Tour before eclipsing Tiger Woods as world number one on 28 March 1999.

And in 2001, he clinched his first major to take the Open at Royal Lytham.

But in 2002, he failed to win a title for the first time since 1996 and by this week, he had plummeted to 437th in the world rankings.