Hunter Mahan fired a final-round 71 to win the US PGA Tour’s US$6 million (RM18 million) Houston Open by one stroke over Sweden’s Carl Pettersson.

Mahan, who won the elite World Golf Championships Matchplay Championship in February, became the first two-time winner on the US tour this year.

The victory will boost the 29-year-old to fourth in the world rankings, sending him into the Masters, the first major tournament of the season that starts on Thursday at Augusta National, as the highest-ranked American.

“It feels great,” Mahan said. “I’m playing good. I’m glad I’m going to Augusta, it’s really a special place and I’m looking forward to going there.”

Mahan’s one-under 71 at Redstone gave him a four-round total of 16-under 272.

Pettersson also posted a 71 for 273.

South African Louis Oosthuizen, who led by two strokes after the third round, had two double-bogeys in a three-over 75 that left him in third place on 274.

Pettersson, who closed his round with eight straight pars, notched his second runner-up finish of the year, but couldn’t get the victory he needed to secure a berth in the Masters.