Mayweather vs. Guerrero: Conditioning Will Be Key in Megafight

Floyd Mayweather returns to the ring a full year after defeating Miguel Cotto. Robert Guerrero will need to work harder than ever to break down Mayweather's defensive wall. Those two factors ensure conditioning will be key to victory on Saturday night.

Staying in elite shape is one of the main reasons Mayweather hasn't been beaten in 43 career fights. He's always had the confidence that he could outlast an opponent. The longer a fight went, the better his chances of taking control and earning the win.

At the same time, the endurance factor has been a huge mental advantage for "Money." Opponents come into the fight knowing they have to dominate early, but that's also when he's at his strongest defensively. It's the perfect combination.

Mayweather put in the grunt work to make sure nothing changes against Guerrero.

Yet, with a year between bouts, it's impossible to tell exactly how his body will react once the opening bell rings. He's 36 and has been fighting at the professional level for nearly two decades. He's going to slow down eventually. Everybody does.

That's what Guerrero needs to bank on: slight regression from boxing's top dog. If both fighters are at their peak, Mayweather wins the fight handily. He's more talented and has the perfect combination of skills to combat the power of "The Ghost."

If Mayweather isn't up to his usual conditioning standard, however, the door will be open Guerrero. It doesn't have to be a major drop off, just enough so that the underdog is able to execute more of his power punches.

The biggest key for Guerrero is pacing himself. This is the biggest fight of his career, and the tendency in that scenario is to come out flying. The problem is it's impossible to maintain that pace throughout the fight, so he'd be playing right into his opponent's hands.

Instead, he needs to understand that there's a good chance the fight goes the distance. Three of Mayweather's last four fights have gone all 12 rounds. The same goes for Guerrero's last five fights. He must prepare for the long haul. Going for an early knockout would likely backfire.

He's got the power to give Mayweather some problems. He must remain patient, though. His punches must still be having the same impact in the ninth round that they have in the first, which brings the entire fight plan back to conditioning.

Mayweather has fought virtually every type of fighter during his career. Guerrero's power alone isn't enough to phase him. But if he's forced to defend against it for all 12 rounds instead of just five of six before completely taking over, things get a lot more tricky.

Both fighters have the tools to come out on top, with Mayweather holding the edge overall. Conditioning will be the factor that pushes him over the top or allows Guerrero to make it close.