Like a snake slowly trying to shed its skin, Tiger Woods has been struggling to remove old habits as he desperately searches for consistency in his remodelled swing.

Frustrated and bitterly disappointed by his erratic performance at last week's Farmers Insurance Open where he once reigned supreme, Woods has not committed to any tournament beyond next week's Dubai Desert Classic on the European Tour.

While the former world number one has shown flashes of his best since joining forces with Canadian coach Sean Foley in August, he is still prone to sudden lapses under pressure when remnants of his old swing resurface.

"They're very different swings," Woods told reporters after closing rounds of 74 and 75 left him in a lowly tie for 44th place at Torrey Pines on Sunday, a distant 15 strokes behind winner Bubba Watson.

"It's tough. It's one of the things I struggled with when I worked with Hank (Haney) trying to relearn some new things and going away from what I did with Butch (Harmon).

"The old motor patterns are still there, and that is the thing. I'm going to have to fight through that. But I've done it before, and there's no reason I can't do it again," he added.

Woods is working on the fourth swing change of his professional career, having previously completed successful overhauls with former coaches Harmon and Haney.

Although he often sounds like a broken record at news conferences when describing such swing changes as a "process", Woods had been greatly encouraged by his relatively swift progress with Foley.

He ended a dismal 2010 campaign with a solid performance at the Chevron World Challenge, which he hosts in his native California, and was in a buoyant mood at the start of last week following a highly productive off-season with Foley.

"The goal's still the same," Woods said on the eve of the tournament at Torrey Pines where he has triumphed seven times as a professional.

"Try to beat other butts, it hasn't changed," he added.

The world number three made an encouraging start to his 2011 season, recording seven birdies and no bogeys in his first 28 holes.

Thereafter, his form became wildly erratic. By the time he completed Sunday's final round, the tournament leaders had just reached the turn.

"I hit a lot of good shots early in the week, and then it progressively got worse," Woods said after finishing outside the top 10 at Torrey Pines for the first time.

"I've got a lot of work to do," he added.

Once renowned for his short game and uncanny ability to salvage par from awkward spots off the green, Woods said he was not tempted to play the same way as he has done in the past.

"How else are you going to get better?" he added. "You've got to do it (follow the Foley path). It takes reps and it takes reps under competition. You can't be afraid to go ahead and try it.

"Sean and I have been talking about it every night. I can do it on the range, but it's a little different when I've got to bring it out here (in competition) and I've got to shape shots. I've got to hit the ball with the right trajectory."

Asked how he stayed patient, Woods replied: "It's just commitment to change and to moving forward. I got committed to what I'm doing, and I'm not looking back. I'm moving forward.

"That's what I have to do, and that's what I'm doing," added Woods, who has not won a tournament since the Australian Masters in November 2009.