Tiger Woods struggles at Cog Hill

LEMONT, Ill. -- The task of advancing to the Tour Championship became even more difficult for Tiger Woods after a 2-over 73 on Thursday at the BMW Championship.

Woods, who throughout the FedEx Cup playoffs had found himself in the unheard of position of having to perform in order to advance, needs a top-five finish at Cog Hill in order to be among the top 30 who advance to East Lake in Atlanta.

"Well, got to keep plodding along," said Woods, who is tied for 45th. "Right now ... I'm only [6] shots back out of that spot. That's not bad. Guys aren't going low at this place because the greens aren't good enough to go low. Obviously there's a couple players that have played well today, but overall the guys just aren't tearing the place apart."

Woods is 9 strokes behind tournament leader Matt Kuchar, who is atop the FedEx Cup points standings and shot 64. He is 6 strokes behind Retief Goosen and Charlie Wi, who are tied for fourth place and in the likely position where Woods would need to finish in order to advance.

Woods, who is 51st in the points standings, got off to a terrible start, making a double-bogey at the first hole after hitting a poor drive.

From there, it was a struggle. Woods was 3 over par on the front nine, didn't make his first birdie until the 10th hole, failed to make a birdie at the par-5 15th where he was in perfect position to do so, then bogeyed the 18th hole.

"I just didn't have much today," he said.

Woods won the FedEx Cup in the two years he competed in it (2007 and 2009), missing the 2008 playoffs due to season-ending knee surgery. He won the Tour Championship in 2007 and was second last year when he won the overall FedEx title.

The BMW Championship is the sixth and final PGA Tour event of the year in which Woods is the defending champion. Last year he shot a third-round 62 on his way to an 8-shot victory.

But Woods is working on swing changes with instructor Sean Foley. He tied for 12th at the Barclays two weeks ago and tied for 11th last week at the Deutsche Bank, finishes that helped him move from 112th in the standings when the playoffs began to 51st.

"I just started at the PGA, and I think I've done a pretty good job of implementing it and meanwhile playing in some big events," Woods said. "It's not easy, it's hard, a lot of work on the range, a lot of work in the room, just trying to make sure I understand it and understand the fixes.

"I was able to do that today, but unfortunately I got caught in between some of my old takeaways, and as a result I hit some bad shots."

Woods hit just 5 of 14 fairways, only 10 of 18 greens and took 29 putts.

Bob Harig covers golf for ESPN.com.