Casey birdied two of the last three holes to take a share of the lead

FIRST-ROUND LEADERBOARD:
US unless stated
-3 H Mahan, P Casey (Eng), R Sabbatini (RSA)
-2 T Woods, M Calcavecchia, B Weekley, A Oberholser, K Perry, S Appleby (Aus), L Westwood (Eng)
-1 Five players

England's Paul Casey held off a stellar field that includes Tiger Woods to earn a share of the lead on day one of the WGC Bridgestone Invitational in Ohio.

The 30-year-old fired five birdies on a difficult day at Firestone to finish three under alongside American Hunter Mahan and South African Rory Sabbatini.

World number one Woods finished the day just one shot back in second, in a pack of seven that included Lee Westwood.

But Open winner Padraig Harrington struggled, finishing on two over.

606: DEBATE Who will win at Firestone?

"It was a hard day for me," said the 35-year-old Irishman. "I worked hard for the score. Seventy-two is not a bad return but I didn't hit enough fairways.

"I am still in the tournament, although it was annoying to drop one at the last. I got myself into position but I didn't play well enough. I need to get back into things."

He concluded: "I was a long, long way away from what I was in the last round of the Open in terms of my focus. I've got to build back up."

You've read my card on the back... it's a telephone number. But it's a good round, I suppose Colin Montgomerie

Scot Colin Montgomerie, meanwhile, was upbeat despite a topsy-turvy round that included an eagle, four birdies, three bogeys and a double bogey that left him one over.

"You've read my card on the back," said the Scot. "It's a telephone number. But it's a good round, I suppose. Don't ask me how.

"When three (under) is leading, one over is okay. There's nothing wrong with that, we'll see how we go. It's not easy out there."

England's Justin Rose was also well placed on one under, and he said: "I've had some treatment on a niggling wrist injury. It hasn't caused too many problems but that was a good round under the circumstances."

Mahan shrugged off a double-bogey six at the 17th, his eighth hole of the day, to surge up the leaderboard.

"I wasn't really happy with myself there but, other than that, I played as good on about 17 holes as I could."

Woods, bidding for a third successive title at Firestone, said: "I hit the ball pretty good today, just had a couple of loose ones, and my short game was decent.

"I thought I had a pretty good touch on the greens. I do feel comfortable around here, I don't know what it is.