Grispi, who went 4-0 during his time with the WEC, was originally set to fight for the featherweight title against undisputed champion Jose Aldo on the same card, but an injury to Aldo forced the Brazilian out of the contest.
In search for a replacement for Grispi, the UFC decided to give Poirier a call, asking if he would like to drop to featherweight to take the fight. Fortunately, the call could not have come at a better time for the Louisiana native.
"I’ve never fought at 145 before, but I was thinking about it," Poirier stated on the latest HeavyMMA Podcast. "Me and my manager were talking about it after my last fight. You know, I’m kind of a smaller 155'er, but me and my trainer Tim Credeur were talking about it and that was probably my next step. And then I got the call to fight (at featherweight), so it was just perfect. I planned on going there regardless."
While Poirier had the intention of dropping down to the featherweight division even before receiving the call, even he was shocked when he was offered a bout with the man who was supposed to challenge for the 145 lb. title.
At 14-1 as a professional, Grispi has been dominant in the sport, and Poirier, who was surprised to get the offer, jumped at the chance to face him. After all, defeating a fighter like Josh Grispi would present huge opportunities in the future for the 21-year-old.
"At first when I got the call, I was thinking, ‘Wow, is this even real?’ I don’t understand why they would call me when they have all these other guys. But I was just excited. I hopped on it. You know, why not?"
Since taking on the match up on short notice, Poirier has been studying his upcoming opponent, watching film from Grispi's recent fights in the WEC, though there is not much tape to study.
In his last four contests, Grispi has finished all four opponents in the opening frame. In those bouts, he has spent less than seven minutes total inside the cage, which is an intimidating statistic for anyone facing Grispi. But Poirier has been taking notes and, he believes, that he can be the man to test Grispi and put his back up against the wall.
"I’ve been watching a lot of video on him," Poirier stated. "I think he’s a great athlete and he’s quick. He seems like he’s very strong, very big for 145. He seems pretty well-rounded. His stand up is decent. I haven’t really got to see his ground game too much."
"We’ve seen him slap submissions on people. We’ve seen him grab guillotines and stuff like that, but I haven’t seen him really transition too much on the ground. And I haven’t really seen him have to dig himself out of trouble either. You know, I haven’t really seen him get caught with any big shots."
While Poirier understands that Grispi's ability to battle back from adversity is a mystery at this point, he knows one thing that is certain; Grispi is a finisher.
With three submissions and one knockout in his last four contests, Poirier is definitely right when stating Grispi is not one to go to the judges' scorecards. However, that is something that makes Poirier even more excited for his fight, because when he faces off against finishers, he feels he will always be the one finishing on top.
"I’ve never seen him fight in person, but I think it’s going to be a good match up for me because he’s a finisher," said Poirier. "He goes in there and he tries to finish the fight, and so am I. When guys fight me like that, I seem to fall in a better spot when we do that."
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