Tiger Woods said he was thankful for getting his mistakes out of the way early as he became the first man in 30 years to win the opening half of golf's Grand Slam.

The prodigious American overcame bogeys on the first two holes, aided by a four-stroke lead when the final round began, and fired a two-over par 72 to finish at three-under par 277.

He was the only player to break par for four rounds. Phil Mickelson, playing on his 32nd birthday, was second by three strokes.

After what happened here in September, for the fans to support me like this makes this moment special Tiger Woods

"I knew I had to tough it out, keep hanging in there, grind my way around," Woods said.

"You're going to make mistakes. I just told myself I got them out of the way early."

By winning his eighth major title and becoming only the fifth man to win the US Open and Masters in the same year, Woods needs July's British Open, and August's PGA Championship to take a Grand Slam sweep.

He has already held all four major titles at once, taking the 2000 US and British Opens and PGA Championship plus the 2001 Masters.

But although the so-called "Tiger Slam" was not a calendar-year sweep, the distinction is lost on Woods.

"I've won the Slam before and I've won four majors in a row," Woods said.

"It's something I'm very proud of. You can call it what you want. This would be a different type of Slam, I guess."

Woods celebrated victory as though it was his first major

After winning $1m for his seventh triumph in the past 11 majors, Woods was in no mood to ponder the Slam.

"Let's celebrate this one. One at a time. This was hard fought against a lot of great competitors," Woods said.

"I'm not thinking about anything. I'm just going to celebrate this. This was hard.

"None of them are easy but this was really hard."

Woods enjoyed winning before a passionately cheering crowd of 42,500 at Bethpage Black, the first public course to host the Open.

"After what has happened here in September, for all the fans to support me like this, that makes this moment special," Woods said.

"Considering what New York and these fans have been through in the past year, that makes it very special."

Woods admitted he was thankful when his nearest rival Mickelson bogeyed the 16th to give him some breathing space.

Woods led by four strokes when the round began and won for the 24th time in 26 events where he has led entering the last round, including eight for eight in majors.