B.J. Penn is officially back, and "The Prodigy," whose work ethic has sometimes been questioned, appears to be as motivated as ever.

Penn told FUEL TV's "UFC Tonight' on Tuesday that a challenge from a hot prospect like Rory MacDonald, in MacDonald's home country no less, was "exactly what I needed."

"I want to go up there [Canada], and I want to show them that, hey, I'm someone to be reckoned with and when I'm standing across you in the Octagon, this is going to be a tough fight," he said. "This isn't going to be a walkthrough. This isn't going to be, let's go push B.J. Penn up against the fence, hold him on the fence for a little bit and now we got him. You know, I got some good ideas going into this camp and I think it's going to be great."

The UFC announced last week that both MacDonald and Penn had verbally agreed to meet at UFC 152 in Toronto on Sept. 22. The main event is slated to be Junior dos Santos vs. Cain Velasquez 2 for the UFC heavyweight title.

Watch Penn talk about his return below.