BJ Penn Planning Return to MMA, Calls out Featherweight Nik Lentz for UFC 197

Those rumors of BJ Penn's return to MMA just became a lot more than rumors.

On Wednesday afternoon, Penn posted a message and photo on his Instagram account that pledged a return to the UFC. The former UFC lightweight and welterweight champ even has an opponent and date in mind: lightweight Nik Lentz on March 5 at UFC 197.

 "This is a formal challenge for Nik Lentz to meet me in the octagon March 5th in Las Vegas," Penn wrote in the post. "Nik, you wrote a silly poem about me making fun of me, you said stuff about me and my parents ... I ask you today to be a man and back up everything you said, talk the talk [and] walk the walk, uncle BJ is mad already."

The 37-year-old Penn (16-10-2) took an extended hiatus from the sport in 2012 and then came back in 2014 to face Frankie Edgar as a featherweight. After taking a one-sided beating that ended in a third-round TKO defeat, Penn formally retired from MMA.

Until, apparently, Wednesday.

The challenge comes just a day after another Penn Instagram post first inflamed speculation of a comeback. Penn posted a photo with famed supercoach Greg Jackson with the caption "we coming!!". 

Not long after, Jackson told Ariel Helwani of MMA Fighting that he had indeed met with Penn and that he was "very optimistic about the future."

Though it is unclear whether UFC officials will actually grant Penn's wish, fans still revere the Hawaii native as one of the best lightweights in MMA history, if not the very best. It stands to reason that many would tune in to watch him fight.

Even so, some fans and media members on Twitter offered a negative reaction immediately following the announcement, saying they did not want to see an aged and diminished Penn risk his health for comparatively little reward. Before retiring, he went winless in four straight and six of his last seven, dating back to 2010.

"

Nik Lentz will hurt him and you will all feel bad about it.

— caposa (@GrabakaHitman) January 13, 2016"

"

I have zero interest in seeing BJ fight again. His fights against Diaz, Rory and Frankie made it painfully clear he's done as a fighter.

— Chris (@mmamaryland) January 13, 2016"

In addition to holding the 155-pound title, Penn also once wore the UFC welterweight belt. Even if he never competes professionally again, Wednesday's communication reads as a clear intention on Penn's part to do so.

For his part, Lentz (26-7-2-1) authored a poem (Warning: Strong language) last fall taunting and threatening Penn. It seems the provocation worked, at least in getting Penn's attention.

If Penn gets his way and returns on March 5, that would add yet another high-profile bout to an already loaded card. Conor McGregor will make his UFC lightweight debut against 155-pound champion Rafael dos Anjos, while Holly Holm makes her first defense of the women's bantamweight title against Miesha Tate.