SAN ANTONIO, Texas, April 7, 2013 (AFP) - The 30-year-old Scotsman matched the course record and snapped a USA win streak on the PGA Tour that dates back to last season.
Rory McIlroy got within one stroke of the lead when he birdied the 14th hole, but the Northern Irishman ended two back at minus-12 after a final-round 66.
Laird, who entered the day five shots adrift of the leader, rolled in birdies on his final three holes Sunday at the TPC San Antonio.
"I felt really good coming here because I like this golf course. I played well here a couple of years ago," said Laird, who finished his third PGA Tour victory at 14-under 274. "I wanted to stay aggressive. Finally, in a final round my putter got hot. I can't believe it."
Laird also earned his third consecutive trip to The Masters. He tied for 20th in 2011 and shared 57th last year in his previous Augusta efforts.
American Jim Furyk holed out for eagle on the par-five 18th for a three-under 69.
He shared third place at 11-under with third-round leader Billy Horschel (71) and Charley Hoffman (69), who birdied six of his final eight holes.
This marks the first time that the Texas Open has served as the final Masters tune-up with the winner getting a free pass into Augusta.
Laird's victory also snapped an American win streak on the PGA Tour which dated back to October 2012.
Last Friday, the tournament got some added firepower when McIlroy decided to join the field which featured eight former major winners and four of the top 15 in the world.
World number two McIlroy finished two shots back of Laird to post his best finish of the year.
"I think over the last three rounds I eliminated the stupid mistakes and mental errors," McIlroy said. "To finish this tournament with a round like today is great going into Augusta.
"I am really pleased with my game this has been a great week for me."
McIlroy birdied the par-five No. 2 then had two consecutives birdies just before the turn on number eight and nine. He caught fire on the back nine with four more birdies over his last seven holes, including the par-five 18. He also had two bogeys in the round.
Leading fourth-round scores here on Sunday in the $6.2 million PGA Tour Texas Open (USA unless noted, par-72):
274 - Martin Laird (SCO) 70-71-70-63
276 - Rory McIlroy (NIR) 72-67-71-66
277 - Billy Horschel 68-68-70-71, Jim Furyk 69-70-69-69, Charley Hoffman 71-67-70-69
279 - K.J. Choi (KOR) 72-67-72-68
280 - Daniel Summerhays 69-69-73-69, Jeff Overton 69-72-70-69, Bob Estes 72-69-69-70
281 - Martin Flores 71-72-70-68, Marcel Siem (GER) 76-67-69-69, Padraig Harrington (IRL) 68-73-70-70
282 - Richard H. Lee 74-70-69-69
283 - David Lynn (ENG) 72-70-71-70
284 - Kevin Chappell 75-69-72-68, Aaron Baddeley (AUS) 74-70-71-69, Freddie Jacobson (SWE) 70-74-71-69, Jason Kokrak 74-68-72-70, Shane Lowry (IRL) 70-72-72-70, D.J. Trahan 70-71-71-72, Ryan Palmer 71-71-68-74