Former opponent Chad Mendes explains the biggest challenge facing Conor McGregor at lightweight

March 5 won't be the first time Conor McGregor has fought at lightweight but it will be the first time he does so on the biggest stage of all.

'The Notorious' won a world title at 155 lbs back in 2012 but neither the stakes, nor the opponents, were at the level they'll be at for UFC 196. Much has been made of how McGregor's power and speed will translate to the UFC's lightweight division, especially against an opponent of Rafael dos Anjos' quality. One man who has felt McGregor's power at featherweight is Chad Mendes, who lost via second round TKO when the pair met for the interim belt last July. 'Money' was asked for his opinion on McGregor's move up to lightweight on last week's episode of Chael Sonnen's podcast and he wasn't so sure that he will be able to carry his assets up to 155 lbs. "I think, just looking back on wrestling, when you go up a weight class and you're wrestling guys that are 10 lbs bigger than you, especially 10 lbs of muscle bigger than you, that makes a huge difference," Mendes said. "When I got in there and fought Conor, Conor's quite a bit bigger than I am, and that's something that takes energy out of you. You're pushing against more muscle than you normally are. That's something that tires you out. "And now with Conor going up there fighting guys that are the size of dos Anjos, in my opinion, it could weigh him down a bit. "Conor's fast at 145 lbs because he's long, he's leaned out. I'm curious to see what his body's going to look like, if he's going to be holding a little bit more body fat or if he's going to be shredded. "I think that if he's holding on to a little bit more body fat, he might be a little bit slower and that could weigh him down a bit too and maybe tire him out a bit. "I think going up a weight class can be both beneficial but also can hurt. In this exact situation, I'm not 100% sure what the hell is going to happen." To refresh everyone's memory, this is how the Dubliner performed at his last trip to lightweight. https://www.youtube.com/watch?v=obgm6JNtyVo