Thousand Oaks, CA (Sports Network) - Graeme McDowell birdied the 18th in regulation and did it again on the first playoff hole Sunday to beat Tiger Woods and win the Chevron World Challenge.

McDowell closed with a three-under 69, while Woods struggled to a one-over 73. The duo ended at 16-under-par 272.

"Those were two of the greatest putts I've made. I've holed a couple nice putts this year, but they were certainly up there," said McDowell in reference to his winning putt at the U.S. Open and the cup-clinching putt at the Ryder Cup. "To play the week alongside Tiger today was pretty special."

Woods, who fell out of the lead with a double-bogey on the 13th, had a kick-in birdie on the 18th in regulation. However, McDowell drained about a 20-footer for birdie to force Woods to make his.

The tournament host did exactly that. Woods tapped in his three-footer and the duo went back to the 18th tee at Sherwood Country Club.

McDowell got lucky in the playoff as his tee shot went through a tree to end in the first cut of rough on the right side. Woods was in the fairway off the tee.

The reigning U.S. Open champion knocked his approach to about 30 feet. Woods dropped his about 10 feet closer. McDowell poured in his birdie putt and Woods missed his on the right side to give McDowell the victory.

"It's just been an amazing year. I can't say enough about it," McDowell said in a television interview. "This was dream stuff this afternoon. To be playing alongside the greatest golfer that's ever played, in his own backyard I suppose, to have a chance to beat him is amazing. I'm ecstatic right now."

Woods had led by four entering the round. The loss means he finished the 2010 season without a victory, be it official or unofficial.

"I fought hard. I fought really hard today," said Woods in a televised interview. "I didn't have it early on the greens. I was hitting it pretty good, but then I lost it with my swing. I pieced it back together. It was close. We had a good battle out there."

Despite a shaky front nine, Woods still led by one as the final duo made the turn. Woods and McDowell parred the first three holes of the back nine before the first big turn of the last nine holes.

McDowell found the par-five 13th green in two strokes, but Woods was making a mess of the hole. Woods found the left rough off the tee, then played his second down the fairway.

Woods hit his third over the green, then pitched back into the rough on the opposite side of the putting surface. Woods finally got on the green with his fifth, but was 15 feet out.

McDowell, who was runner-up to Jim Furyk in 2009, lagged a long eagle putt within tap-in range. Woods two-putted for double-bogey, while McDowell made birdie for a three-stroke swing.

McDowell hit a poor drive on the 14th and that led to a bogey, which cut his lead to one stroke. Woods parred four in a row from the 14th, and McDowell came back to him.

The 31-year-old from Northern Ireland hit his tee shot on the par-three 17th into deep fescue grass. He took an unplayable lie penalty and went backwards to ninth tee.

McDowell pitched to about seven feet and drained the bogey putt. The duo was tied at 15-under headed to the last.

"The four I made on 17 today was something else," McDowell said on television. "I tugged that eight-iron. I was literally 15 feet from the hole, but in a horrible spot. To make four there, and make the two putts on the last green, wow, it's just been that kind of year."

Woods stuffed his approach at 18 to three feet, while McDowell left himself 20 feet. McDowell poured that putt in for birdie and Woods matched him to force the first extra session in tournament history.

"Thirteen was a big swing hole obviously. He picked up three shots there," Woods said. "He made a couple mistakes coming in. I thought 16 was going to be our swing hole, but it ended up being a moot point. Seventeen ended up being the swing hole. Then 18 in regulation, we both hit good shots in there. He made a great putt, then I made mine.

"In the playoff, he made another good putt. I hit mine right where I was looking. I didn't think it was going to be a double-breaking putt."

McDowell was hot early. He birdied the three of four holes from the second to jump to 15-under. McDowell parred the next seven holes before the turning point at 13.

Woods wrapped bogeys at one and three around a birdie on the second. Both of those bogeys were the result of Woods missing par putts from inside four feet. He two-putted for birdie on the par-five fifth to get back to 17-under. Like McDowell, Woods parred seven in a row from the sixth.

Paul Casey closed with his second straight three-under 69 to take third place at 12-under-par 276. Rory McIlroy (68) took fourth at minus-11. Hunter Mahan finished alone in fifth at 10-under-par 278 after a final-round 69.

NOTES: Furyk, the 2009 champion, closed with an even-par 72 to end in 11th place at even-par 288...The final unofficial event of the 2010 season is next week with Jerry Kelly and Steve Stricker defending their title at the Shark Shootout.