Woods has two US Opens amongst his 12 major titles

The world number one started his Oakmont challenge by driving into a bunker and bogeying the 1st.

He then birdied the 2nd and 6th to get under par but more inaccuracy off the tee led to bogeys at eight, 10 and 12.

The 31-year-old American got a shot back at the short par-four 17th and seemed relatively happy with his 71.

"I felt pretty good - and hit it consistently all day," he said. "It was conservative but that is the way you have to play US Opens.

"It's right there - three, four, five over par, you're still in the tournament. You've got to hang in there.

It's a really good score to be one over Geoff Ogilvy

"This golf course is hard. It's hard to make birdies and it's easy to make bogeys and doubles.

"Nobody's taking it to the golf course. This was as easy as it's going to play, and look what happened."

That said, the 12-time major winner's play up the last summed up his day at the tricky Pittsburgh course. He smashed his driver into the rough, hacked his ball forward into more rough short of the raised green but got up-and-down beautifully to save his par.

Playing alongside Woods was defending champion Geoff Ogilvy, and the Australian matched the 2000 and 2002 US Open champion's opening effort.

The 30-year-old made just 10 pars in a topsy-turvy round that included four birdies, three bogeys and a double bogey.

606: DEBATE I expect Woods and Mickelson will be there or thereabouts as always SR

"It wasn't crazy difficult this morning," Ogilvy said.

"It's hard when you get off track. When you're on track it's OK. Every time I was in the fairway I did OK. Every time I was in the rough, it was hard.

"It's a really good score to be one over."

Ernie Els, another two-time US Open champion and the winner the last time the tournament was played at Oakmont in 1994, will be less pleased with his opening 73. The South African mixed two birdies with five bogeys.

Scottish amateur Richie Ramsay, the third member of the Ogilvy-Woods group, carded an eight-over 78.