The fighter expressed his frustration with the loss at the post-fight press conference, admitting that he was emotional.
“This might be it, man,” Thomson said. “You train this hard for this long. I just see my title shots [expletive] disappearing.”
The main event between the two fighters had one judge, Gabriel Sabaitis, scoring the fight 48-47 in favor of Thomson. The other two judges gave the nod to Henderson, including Sal Damato scoring it 49-46 in favor of the victor.
While the loss was the key reason behind Thomson's frustration on Saturday night, the consideration for retirement started before UFC on FOX 10 began. Thomson said he considered taking the steps towards hanging up the gloves around the time he was offered a title fight with current UFC lightweight champ Anthony Pettis.
When Pettis had to pull out of their scheduled title fight, Thomson gave some thought into calling it quits.
“I've had this all in my head. A 15-, 16-week camp will do that to you,” he said. “I'm no spring chicken, so you start thinking about it. Two practices a day for six days a week, 16 weeks; that's an NFL season. I get hit more than guys in the NFL and they get paid way more.
“Everybody needs to know [when] their time has come. Maybe it's not mine right now, but I also don't want to be that person that fights not knowing when it's time to quit.”
Thomson compared Saturday's loss to the close fight he had with Gilbert Melendez in Strikeforce. He said he can see how the Melendez fight could have been scored either way, but added that the Henderson fight, although close, was one that he felt he had definitely won.
“I beat the former UFC champion,” he said. “The guy was here for two years, and I beat him with one hand. That's what I can't stomach. I'm a better fighter. That's what pisses me off.”
While he indicated it's something he's considering, Thomson wouldn't commit to full-on retirement in the moments after the UFC on FOX 10 loss. The final decision about his career will come after some discussions with those close to him and talks with other important figures.
“Realistically, I'm just going to go home, have a talk with my family and talk with my coaches, and I'm probably going to sit down with Dana and see which direction we want to go,” he said. “That's really what it comes down to is just getting the whole team together, seeing what the plans are for me.”
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