Conor McGregor is the biggest name in the UFC, and he might be leaving the sport. At the age of 27, do you really believe he's done fighting?

Dana White is probably hysterical somewhere, hoping this is all a joke.

First, Rhonda Rousey walks away from the UFC with a ton of money, now Conor McGregor follows suit. Before we jump to conclusions, take a look at McGregor's tweet that set off this firestorm.

Does that sound like a guy making the most significant decision of his life? "Catch ya's later." Pretty nonchalant...

Now, that being said, the "Thanks for the cheese" part is legit. Even in his loss to Nate Diaz, he became the first UFC fighter to pull in a million dollar purse for a fight. He raked in tons of cash fighting for Dana White in the Octagon, so he might be ready to walk away. He could also be using this as a negotiation tactic to get even more money out of White and the UFC.

There are a lot of reasons to doubt his retirement announcement, but there's another big factor in play here: his health.

One of the strongest arguments for believing in McGregor's retirement is a matter of mortality. He watched a man die in the ring, and it affected him heavily. We've seen athletes walk away from sports at a young age, even at the peak of their game. Watching Joao Carvalho lose his life might have been all it took to change McGregor's mind about the sport he loves.

After watching the fight, McGregor posted this to Facebook:

"Terrible news regarding Joao Carvalho.
To see a young man doing what he loves, competing for a chance at a better life, and then to have it taken away is truly heartbreaking.
We are just men and women doing something we love in the hope of a better life for ourselves and our families. Nobody involved in combat sports of any kind wants to see this. It is such a rare occurrence that I don't know how to take this."

Is McGregor responding to an interaction with the spectacle of death with this retirement, or is it something else?

We're going to need some clarification, Mr. McGregor. "Thanks for the cheese. Catch ya's later." That's not going to cut it in the explanation department. And there's a call for you on line one, it's from Dana White...