Duffy expects rematch with McGregor in 2017: 'I think we can sell out Croke Park'

The specter of Joseph Duffy continues to loom large over Conor McGregor.

With his brilliant mix of brash, pro wrestling-esque antics and highlight reel finishes, McGregor has not only become the UFC's premiere featherweight, but he's transformed himself into the promotion's biggest draw.

Unfortunately for the "Notorious" one, Duffy's mere presence on the UFC's roster is slowly eating away at his mystique.

Years prior to their respective debuts on the big stage, Duffy handed McGregor his most recent professional loss, when he submitted his Irish brethren via rear-naked choke at a Cage Warriors event in 2010.

Now, with McGregor teasing a move up to lightweight, Duffy-McGregor II is a very real possibility.

"I think he'll do well," Duffy told MMAFighting.com's Ariel Helwani about McGregor's potential move to lightweight. "You know, Conor's a good fighter. He's a good fighter and he's got very good striking that ... I think people underestimate. I think they underestimate how good it is.

"There's rumors that he's going straight in for the title. I'm not sure if that's true. You know, it's an interesting time."

Naturally, Duffy isn't thinking small for the potential rematch.

"Without a doubt I think we can sell out (Ireland's) Croke Park," Duffy said. "I feel by the end of the year people are going to be talking a lot more about that fight. I don't think (it happens in) 2016. I think 2017."