Georges St-Pierre is as qualified as anyone to comment on the highly anticipated UFC 183 main event between returning former longtime middleweight champion Anderson Silva and his fellow returnee, former Strikeforce welterweight champ Nick Diaz.

St-Pierre was Silva's contemporary for years atop the sport's pound-for-pound polls, and he fought Diaz, defeating him via decision at UFC 158.

And while St-Pierre gives Diaz plenty of respect, he believes Stockton's most famous athlete made one mistake: Accepting the bout at 185, Silva's natural weight class.

"To tell you the truth, I would maybe favor Diaz if the fight had been at a catchweight," St-Pierre said on a recent edition of Chael Sonnen's "You're Welcome" podcast. "Because if it is a five-round, Diaz is a very durable fighter. I have seen him in a lot of trouble and he is very, very hard to finish."

But GSP believes taking the fight at middleweight tips the scales against Diaz, a fighter who has competed as low as lightweight over the course of his career.

"Now it is different because it is in Anderson Silva's weight class," St-Pierre said. "Which I believe Diaz made a mistake at accepting that fight at 185 instead of, I think he should have made a catchweight would have been more fair.

Still, St-Pierre believes that if Diaz can weather Silva's early storm, he'll have a chance.

"I believe that in the early part of the fight that Silva will have an advantage. But if Diaz can survive will weather the storm, I believe he can come back strong at the end, the last part of the fight, maybe the fourth and fifth round. He's a very durable fighter and he brings to the fight, when you fight, he's talking to you, and he brings a different intensity that I've never seen seen before. And I felt like a little bit, you feel claustrophobic a little bit because he's constantly pushing you forward and it's very hard to fight a guy like him. Especially in the later rounds."

For Silva, GSP sees the key to victory as being as simple not getting goaded into Nick Diaz's favorite type of fight.

"He's a very, very smart fighter," St-Pierre said. "He says, his image and the character that he is, he's very smart. My game plan when I fought him was to not fall into this because it was important. If I fell into it and get into a slugfest with him, it would have been his fight. I would have fought his fight and he probably would win. You know, he's a scrapper, slugfest, that's when he's at his best."