Henderson (21-5) is stepping into deep waters at the 1stBank Center against the bigger Thatch, a dangerous striker who has made short work of his opponents.
Thatch was originally slated to face Stephen (Wonderboy) Thompson on the televised card in Broomfield while Henderson was matched against Jorge Masvidal on April 4 in Fairfax, Va. But when Thompson injured a rib in training, Henderson stepped up.
"I've always said anyone, anywhere, any time, any place," said Henderson. "But it's hard to do that."
Hard when you're champion, anyway. The 31-year-old Arizona-based fighter said UFC matchmaker Joe Silva and president Dana White would laugh when he offered to fill in as needed while he was atop the 155-pound division.
Having lost his title to current champion Anthony (Showtime) Pettis at UFC 164 in August 2013, Henderson is still willing and now able to be more flexible.
"We have a short time in the fight game," he said. "So make the most of it."
It speaks volumes about Thatch (11-1) that he is getting a main event fight in his home town after spending just three minutes 33 seconds in action for the UFC. But during that time he demolished Justin Edwards and Paulo Thiago.
In his short UFC career, he has landed 8.17 significant strikes per minute, compared to 2.88 for Henderson, according to FightMetric.
But a string of injuries have sidelined the 29-year-old Thatch since the win over Thiago in November 2013. Most recently a compound fracture of his toe prevented him meeting Jordan Mein of Lethbridge, Alta., last August.
All of Thatch's victories came in the first round with six lasting less than a minute. His lone loss came via decision in his second pro fight, against Brandon Magana on a September 2008 Strikeforce card at the Playboy Mansion.
Henderson has lost his last two fights, in radically different circumstances. Against Rafael Dos Anjos last August, he was stopped in the first round after a left hook dropped him.
Henderson believes the stoppage was premature, but he's not complaining. That's not his style.
More recently, he suffered a controversial decision loss to Donald (Cowboy) Cerrone on Feb. 14 in Boston. FightMetric had Henderson outstriking Cerrone each round with an overall 86-57 edge in significant strikes. But the judges saw it differently.
Again Henderson has no beef.
"As fighters, all we can do is go out there and do our best. We don't control the judges."
At six foot two, Thatch will have a five-inch height advantage on Henderson. The former champ, however, says he will have the edge in speed and agility.
Henderson, who has fought at 170 pounds earlier in his career, says he probably could have made 155 pounds despite the short notice "but I would not have performed well at all." He says this welterweight fight is a "one-time thing for right now."
NOTES: Alexis Davis and Sarah Kaufman will meet in an all-Canadian bantamweight bout at UFC 186 in Montreal on April 25. Davis is ranked third among 135-pound contenders while Kaufman, a former Strikeforce champion who beat Davis in 2007 and 2012, is No. 5 ... Two former champions will face off in the main event of the UFC's first trip to the Philippines on May 16 when former UFC world lightweight champion Frankie Edgar takes on former WEC featherweight title-holder Urijah Faber at 145 pounds. Montreal-based lightweight (Ragin') Kajan Johnson will fight China's Zhang Lipeng on the televised fight card in Manila.
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