Moments after the win at the Golf Club of Houston, the Brit said: "Last week was painful".
"To come here this week, I was exhausted, I was frustrated", said Poulter, who packed his bags after shooting 1 over on Thursday, assuming he would miss the cut.
Poulter had further reason to feel aggrieved after a mix-up saw him informed that he had done enough to qualify ahead of his quarter-final at the WGC-Dell Technologies Match Play, only to be told 10 minutes before his defeat to Kevin Kisner that he required another victory. Poulter held the lead most of the final round before losing it on the back nine.More news: A life of struggle — Winnie Madikizela-Mandela
Ian Poulter resurrected his stagnant career by winning the Houston Open in a playoff on Sunday, the victory coming with an added bonus of earning the final invitation to the US Masters and throwing his hat into the ring for Europe's Ryder Cup team.
A fifth birdie of the day at the 11th put Poulter back in command, but Hossler then took centre stage as he holed some excellent putts in his run of four straight birdies from the 12th. "I had packed my bags to leave on Friday night, and had a mental switch", Poulter said.
Just last week, towards the end of the WGC Match Play, Poulter was told he had earned himself a spot in the Masters when in fact he had not.More news: Spring storm packing heavy snow
The 42-year-old Englishman had forced a sudden death play-off after he sunk a lengthy birdie putt at the 18th to finish at 19 under alongside Hossler. "To do it this week, after the disappointment of last week, to know I'm going to Augusta, to do it in true fashion, is unbelievable".
Jordan Spieth warmed up for the Masters by closing with six-under 66 to share third place with Argentina's Emiliano Grillo (68) on 16 under. He will likely now move into the world's top 30, with a Ryder Cup appearance in France later this year suddenly highly likely.
"It's been a rollercoaster the last couple of years to be honest, to be down where I was has been tough". That's as low as I've ever been, that's as far down the world rankings as I've been, questioning whether you've got a Tour card or not - it isn't very good.More news: Malala Yousufzai visits hometown in northwest Pakistan
That sort of putting wins Green Jackets, not just warm-up events.