With 17 professional fights under his belt including a short-lived 170-pound title reign, the 38 year-old decided he had enough of the hurt business on the heels of losing three of his last four bouts.
And while he would have liked to have at least one more fight inside the Octagon, Serra says he didn't want to do it just to do it.
Furthermore, the Brazilian jiu-jitsu black belt reveals he will miss the "high" a fighter gets after going through a tough battle or after earning a victory. It's the absence of that feeling that Matt believes is the reason why many former fighters turn to drugs in attempts to fill the void.
He explained during his recent appearance on "The MMA Hour:"
"Let me tell you. It was always the plan to do one more at least. But, you don't want to just do it to do it. Like, if I watch UFC and I see something, I'm like, ‘Fuck man, I miss that.' The feeling is, like you see all of these guys, well some, not all of these guys, especially like the real warriors man, they stick around a lot of time longer than they should. It's not even about the attention, it's not about that. It's that feeling of fighting in there. It's really something man. That's why I think fighters, you know, post-fighting they turn to drugs and they turn to this and turn to that because they are missing something. They need that high, you know what I mean? It's such a high. Like when you win or have a battle in there, or whatever."
His decision to walk away from the sport seemingly popped out of nowhere, revealing that he never had a timetable for his final decision, saying it was through a casual talk with a friend at Newsday that resulted in the impromptu announcement :
"I was talking to my buddy Mark and he wanted to do a story about how I was feeling and that the word was out about my health. So it started with me and him just bullshitting because I know the guy, and then it turned into kind of like my retirement piece. And it's cool, listen, it's all good because I meant everything I said and, you know, it's not like I set out to do that. It wasn't my mission that day to wake up and say, ‘You know what, today I walk away."
Serra recently underwent rib surgery after it was discovered he was suffering form thoracic outlet syndrome -- a "disorder Matt describes as "weird" -- in which his collarbone and his first rib was compressing a vein restricting blood flow to his biceps and other areas of his body.
And while he will likely be remembered most for his upset win over Georges St. Pierre at UFC 69, he leaves behind a bevy of memories and entertaining fights for fans to enjoy for the years to come which includes his bitter rivalry with former 170-pound champ Matt Hughes.
What will you most remember Serra by?