In the process, Tate also upset plans for Kiwanuka to fight for the International Boxing Federation title.
HBO Sports was reported to have already begun negotiations to have Kiwanuka meet IBF champion Charles Brewer in March, possibly at the new Apollo of Temple sports arena in Philadelphia, which is expected to be completed before the end of the year.
That was assuming Kiwanuka and Brewer (of North Philadelphia), who defends his title against Boston's Joey DeGrandis at the Blue Horizon on Dec. 2, both won.
And that is no longer the case.
``We're going to try now to get Tate to become the mandatory [opponent], even though he wasn't even ranked,'' promoter J Russell Peltz said. ``Nobody else in the division means anything, and Tate's the man now.''
That's fine with Tate.
``First of all, I was just glad to have the opportunity to fight in the Blue Horizon. It was my first time here and I put on an excellent show,'' the not-so-modest Tate said. ``[Next] maybe I'll fight Charles Brewer for the IBF title back here in Philadelphia. I don't know yet.''
The future is less certain for Kiwanuka, although his trainer, Eddie Mustafa Muhammad, is optimistic the Uganda-born, Las Vegas-based fighter will rebound.
``It's not the end of the world,'' Mustafa Muhammad said. ``This was one great fight, a nip-and-tuck fight. Joseph got rocked and Tate got rocked. It could have gone either way.''
Two judges had the fight even and one had Tate ahead by a point when the knockout came.
``He'll come back,'' Mustafa Muhammad predicted. ``This is just a learning experience.''
``I'm going to take a couple of days off - maybe a few weeks,'' a dejected Kiwanuka said in a whisper. ``Then I'll be back.''
PUNCH LINES Junior welterweight Jermal Corbin (14-2), of Logan, lost a sixth-round technical knockout to Mike Griffith (17-5), of Cleveland . . . Light heavyweight Antonio Tarver (6-0), a 1996 Olympic bronze medalist from Orlando, scored a third-round TKO over Benito Fernandez (17-8), of Spartanburg, S.C.