George Zimmerman's One-Time Defender & BFF Frank Taaffe Wants To Fight Him In The Boxing Ring: 'I Put Myself On The Line And Feel Like He Used Me'

George Zimmerman's boxing bout with rapper DMX was called off after the   organizer pulled the plug, but RadarOnline.com has exclusively learned that hasn't stopped opponents from asking for a chance to fight the acquitted killer — and the latest is his one-time pal and key witness, Frank Taaffe.

Zimmerman's former best friend and biggest defender during his first-degree murder trial of teenage Trayvon Martin has had a change of heart and World Xtreme Entertainment CEO Damon Feldman tells RadarOnline.com it's because the two had a falling out.

"They were neighbors and friends, but now Frank wants to fight George in the boxing ring because numerous phone calls to George have gone unreturned," Feldman said.

And Taaffe tells RadarOnline.com, "I feel like I was used and not treated fairly by George."

"I was always there for him," Taaffe continued. "I backed him through this whole fiasco and now he is nowhere to be found. I put myself on the line for this guy."

Taaffe tells RadarOnline.com he wants to get Zimmerman in the ring — and even calls himself "the white Al Sharpton."

"I saw that he wanted to do a boxing match, and I want George bad. This is the way to settle this legally…in the ring," Taaffe said.

"I am the white Al Sharpton. I love everyone and I am just very out spoken. I plan on knocking Zimmerman out for what he did and for turning his back on me .

If Zimmerman agrees to the match, it will go three rounds.

It was RadarOnline.com who first reported that Zimmerman has been training in the boxing ring and would like to enter into a bout with a celebrity to raise money for a charity.