Resurgent McIlroy upstaged by unlikely Laird charge in Texas

(CNN) -- While Rory McIlroy was steadily playing himself into form for this week's Masters, an unexpected challenger came through to earn a place at Augusta with a shock win at the Texas Open on Sunday.

Scottish golfer Martin Laird fired nine-under-par 63 in the final round, with birdies at his last three holes, to end McIlroy's hopes of a morale-boosting victory.

The world No. 2, who canceled a humanitarian trip to Haiti last week to make a late entry in San Antonio, had to settle for second place after closing with 66.

"Even though I didn't get the trophy, Martin was just too good today -- 63 in these conditions is just phenomenal," McIlroy said.

It was his best finish in the U.S. since winning last September's BMW Championship, which helped the Northern Irishman top the money list before adding the European Tour title to his swag.

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"I'm really pleased with my game and I think this has been a great week for me," he said.

The 23-year-old has struggled this season following his reported $250 million switch to Nike equipment, and surrendered the No. 1 ranking to Tiger Woods last month.

"Just eliminating the stupid mistakes that I was making on the course, mental errors, and to finish off this tournament in the way I did today is great going into Augusta," McIlroy said.

Laird triumphed by two shots as he earned his third PGA Tour win, and his first since 2011, as he ended a run of 14 American winners on the PGA Tour this season.

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The 30-year-old, ranked 117th in the world before this tournament, had missed the cut in half of his eight starts this year, with a best finish of 34th.

"It's unbelievable. I've been asked probably 30 times in the last couple of weeks 'Are you in Augusta? Are you in Augusta?' and I've had to say 'No' and every time it kind of hurt me a little bit after playing the last couple," Laird said.

"So that was my major motivation to try to get back into tournaments like that this year, and this win goes a long way in doing that."

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Overnight leader Billy Horschel missed out on his first victory -- and a Masters debut -- as a 71 left him three shots behind Laird.

He tied for third with 2003 U.S. Open champion Jim Furyk and another American, Charley Hoffman -- who both shot 69.

Veteran Korean K.J. Choi was sixth on nine-under 279, five shots off the winner.