Englishman Poulter parred the first extra hole to beat American Hossler after the pair had shot matching 67s to finish regulation at 19-under-par 269 at Golf Club of Houston.

Poulter sank a 20-foot birdie putt at the last hole to force the playoff.

He punched his chest in excitement after his putt dropped in, a minute after Hossler's ball had grazed the hole with the American's own birdie attempt that would have clinched victory at the par-four 18th.

Hossler then handed the win to Poulter in the playoff when he thinned his third shot from a greenside bunker into a water hazard.

Poulter arrived in Houston needing a win to qualify for the Masters, after missing out by a whisker when he found himself 51st in the world rankings last week.

Poulter poses with the winner's trophy after winning the Houston Open at the Golf Club of Houston. PHOTO: Stacy Revere/Getty Images.

The top 50 at the cutoff last Monday earned exemption to Augusta.

For Poulter it was a first stroke-play victory in America, but it was a place at the Masters which gave him most cause for celebration.

"It is amazing, to get this done today to get me to Augusta is amazing," he told Sky Sports.

"I'm going to have a good day's rest tomorrow, I will not be venturing to Augusta until Tuesday.

"It's going to take a little while to sink in. I'm super excited.

"It's been a rollercoaster the last couple of years to be honest, to be down where I was has been tough."

Poulter and Hossler finished three strokes ahead of American Jordan Spieth whose closing 66 saw him secure third place with Argentine Emiliano Grillo.

Matt Jones was the best of the Australians, shooting an impressive final round four-under-par 68 to finish tied for 52nd.

After his whirlwind third-round 65 which rocketed him to joint third position, Greg Chalmers shot a disappointing nine-over-par 81 to finish in a tie for 70th.