Chael Sonnen Claims 'Hack' Wanderlei Silva Still Hasn't Signed Bout Agreement

Three-time UFC title challenger Chael Sonnen is currently filming Season 3 of The Ultimate Fighter: Brazil opposite rival Wanderlei Silva and the two are set to square off at the end of May. 

However, according to "The American Gangster," his arch nemesis is yet to sign on the dotted line to make their long-awaited grudge match official. 

"

If you wanna dance you gotta pay the band. If you wanna sing you gotta be the man.Cant retire this hack Until he signs the contract. #sign

— chael sonnen (@sonnench) February 25, 2014

"

According to an interview with Brazilian media outlet Combate (h/t MMA Mania), Sonnen echoed a similar sentiment, stating he would "get rid of this bum" before moving back to middleweight. 

Sonnen and Silva were originally slated to settle their differences in the co-main event of UFC 173 in Las Vegas, but the fight was instead pushed back a week to headline a Fight Night event in Brazil, per MMA Fighting. 

The bad blood between the well-known competitors has been brewing for over two years now and has already come to a head during an impromptu scrap on the TUF set, also per MMA Fighting. 

Sonnen has come up short in all of his bids for UFC gold in the past three-and-a-half years, losing to then-middleweight champ Anderson Silva (twice) and Jon Jones. 

Despite failing to reach the pinnacle of the UFC's middleweight or light heavyweight division's, the Team Reign Training Center fighter is 6-2 in non-title bouts since February 2009. 

Most recently, the charismatic grappler came up short against ex-UFC champ Rashad Evans at UFC 167 in November. 

On the other hand, "The Axe Murderer" is 4-5 in his past nine matchups since returning to the Octagon December 2007, though he is coming off a vintage knockout over Brian Stann at UFC on FUEL 8 in March. 

Will Sonnen vs. Silva actually go down as planned on May 31 or will some drama behind the scenes deprive the fans of this intriguing fight?

John Heinis is a featured columnist for Bleacher Report. He is also the MMA editor for eDraft.com.