The 29-year-old Dunne, a strong favorite backed by the home crowd, was knocked down three times in the round before referee Jean-Louis Legland stopped the 02 Arena contest at 2:57 minutes.
The vanquished Dunne, who needed a last minute KO to wrest the world title off Panamanian Ricardo Cordoba last March, vowed that he’d be back.
It’s going to take a long time to get over this but I will get over it,” pledged the 29 year-old, whose record dropped to 28-2 [15KOs].
Poonsawat [39-1, 28 KOs], who’s 28, said he knew early on that he could beat the Irishman.
It didn’t look so after the first round and a half when Dunne dominated with his jab. However, in the second stanza, Poonsawat rocked the champion and then sent him to the canvas with a jarring left hook early in the third.
Back on his feet, Dunne made the cardinal sin of attempting to trade with the hard hitting Thai. Another left hook followed by a right hand decked him again and after a third trip to the deck the match was over.
The Irish boxer was a victim of the three-knockdown rule, but dazed and bleeding from both his left ear and from a cut near his eyebrow, he was in so fit state to continue anyway.
Said Poonsawat: “The first and second round I tried to get close to find out his style and after the second I knew I could beat him and just pushed harder and harder.”
Brian Peters, Dunne’s promoter, hinted at a move up to the featherweight division and backed his charge’s ability to stage a come-back.
“I firmly believe Bernard Dunne will be back,” Peters said.
In a reference to the death of Darren Sutherland, Dunne said: “I just wanted so badly to lift people, to give them and Irish boxing some joy. I knew what to expect and I just fought back. It was my own stupid fault.”
On the undercard, Dubliner Oisin Fagan got off the deck to demolish Latvian super featherweight Juris Ivanovs in 30 seconds of the second round. Fagan, a former Oklahoma resident, upped his ledger to 24-7 [15 KOs].
Another Dubliner, IBF International titlist Patrick Hyland [18-0 , 9 KOs], scored a sixth round TKO over Venezuelan Manuel Sequera in their featherweight scrap.
Middleweight Matt Macklin won the vacant European title with a first round stoppage of former champ Amin Asikainen of Finland at the Velodrome in Manchester, England.
Macklin [25-2, 18 KOs] starched Asikainen with a left hook at 2:34 minutes of the opener to win his eighth straight bout.
Irish-American light welterweight Danny O’Connor [9-0, 3 KOs] was an impressive third round KO winner over Patrick “The Raging Bill” Cape [6-8, 3 KOs] in Manchester, New Hampshire, last Wednesday.
A 2008 U.S. Olympic Team alternate, O’Connor caught Cape with a perfectly placed left uppercut to the body.
“LITTLE MAC” ADDITION
John Duddy will have Irish company on the “Island Warriors: Latin Fury 12” card at Madison Square Garden’s WaMu Theater October 10 in lightweight Danny “Little Mac” McDermott.
The Jersey City prospect [8-1, 3 KOs], will face the undefeated Hector Marengo [5-0-3, 3 KOs] of Aricebo, Puerto Rico. Duddy is in the co-feature against Michi Munoz.
Tickets are priced at $250, $150, $75 and $50, and are available at the MSG box office as well as from Greg McIntrye at (917) 528-7379, Barney Moore at (917) 559-8467 or from www.duddyboxing.com.