UFC 189 will be headlined by Conor McGregor and Jose Aldo, and part of the talking points on the highly anticipated match up has been on the Irishman's grappling skills. While we have all seen his striking prowess, Conor's jiujitsu skills has largely been an unknown commodity for most fans.

In the past, Eddie Bravo has given McGregor high praise after training at his gym, while his coach John Kavanagh has boldy stated that we shouldn't be surprised if his pupil submits Aldo.

Now, his primary training partner in Gunnar Nelson has also weighed in on the topic. The highly decorated black belt has also vouched for McGregor's skills on a recent appearance at Submission Radio.

"He’s very good on the ground, and he’s even better when it’s grappling for MMA," Nelson said about McGregor. "That’s a lot of difference. You know, grappling or Jiu Jitsu is not the same as the wrestling and grappling in MMA, and he’s really good there. He’s got good submissions, he’s very fast and he can move in most directions"

"He’s getting better every single day. So yeah, I’m sure if a good black belt forgets himself for a second, he’s on you and he’s probably going to submit you."

When asked point blank if he thinks it's possible that he submits a BJJ blackbelt in Aldo during their fight, "Oh, one hundred precent he can."

Watch the entire interview above where Nelson also talks about his match up against John Hathaway, which happens on the same card as his teammate.