For the first time in a long time, a UFC event is being overshadowed – in a very big way – by a good old boxing match. It’s not that surprising, really – UFC 103 is a lousy card full of less than captivating fights without headline names, while the boxing match features the return of one of the top fighters of this or any time after a two year break against a stellar pound-for-pound star.

Floyd Mayweather Jr. is obviously the big draw. Money has been flawless in his career – 39-0 with 25 knockouts, and he hasn’t ducked many fighters en route to that record. He has held six titles at five different weight classes, and he’s only 32 so he still has lots of fight left in him. Juan Manuel Marquez is slightly older at 36, and less successful at 50-4-1. He has held titles at three different weight classes and is currently ranked second in pound-for-pound rankings.

This fight is being contested at a catchweight of 144 pounds. That’s a jump up in weight for Marquez – he last fought at lightweight, which tops out at 135 pounds. Mayweather last fought at 147 pounds, and he has fought well below that in the past, so he is in his comfort zone here.

So, who is going to win? Needless to say, Mayweather is the popular choice. 5Dimes has him at -410, leaving Marquez at +330. Virtually everyone out there is predicting Mayweather will remain unbeaten. I think that the most likely outcome is that he will win as well. I can’t accept, though, that this line is accurate. Marquez is an underdog, but not nearly as much of one as this line suggests. Here are five reasons why:

1. Weight – Marquez is a big puncher who has knocked out his last two opponents. He relies on those heavy fists more than he does on being nimble. As such, I think that the extra seven pounds are going to be an advantage for him – more oomph to put behind the punch.

2. Tenacity – This fight is going to be a war. Marquez has much more experience with picking himself off the canvas and continuing. I know that Marquez will handle a setback with determination and vigor. I can’t be quite as convinced about Mayweather. Money doesn’t seem like a guy who likes to get dirty, so Marquez has an edge if this one gets ugly.

3. Finishing ability – Mayweather is fit, but Marquez is fitter. Marquez has an amazing ability to get stronger the more he gets hit – His best rounds seem to come at the end of fights when his opponents are tiring. there is a good chance that this one will go the distance or close to it, and that works to Marquez’ favor.

4. Current form – Mayweather hasn’t fought in two years. That means that there will be inevitable rust – it’s been a long time since he took a real punch. Marquez has won two big fights impressively in just over a year. Before that he lost to Manny Pacquiao, the current pound-for-pound king, in one of the most ridiculously unjust decisions we’ve seen in a long time.

5. Personality – Marquez is a total professional – he just puts his head down and does his job. Mayweather is a massive ball of charisma, and he surrounds himself in drama. that’s all ramped up to a new level this time around now that he has reunited with his father and has him in his corner. At this point in their careers I have much more confidence that Marquez will have his head in the right place than Mayweather. In other words, I know what we will get from Marquez, while Mayweather could give us anything. That intangible quality gives Marquez an edge.

What does that all boil down to? I’m not willing to come right out and call for the upset. I do think, though, that there is all sorts of value in betting on Marquez – over the long term a bet on the brawler would be profitable.