It was one of the greatest heavyweight fights in the history of mixed martial arts. But as shocking as it is, in a sport loaded with rematches, all-time greats Fedor Emelianenko and Mirko Filipovic only went toe-to-toe once, with “The Last Emperor” taking a unanimous decision in 2005.

But even though both men are well past their physical primes, it appears as though "Cro Cop" and Emelianenko could lock horns again. According to a new poster from Japanese promotion Rizin Fighting Federation, Fedor and Cro Cop are likely participants in a rematch on Sep. 25. The league has previously announced an open-weight tournament for the event.

There are no details whatsoever regarding the proposed fight, other than the heavyweights' likeness plastered all over the poster.

The heavyweight popularly known as “Cro Cop” announced his retirement late last year before he was to face Anthony Hamilton at UFC Fight Night in Seoul, citing a shoulder injury that left him unable to raise his arm. Shortly thereafter, it was revealed that Filipovic had been flagged for an anti-doping violation.

The Croatian was ultimately suspended for two years by USADA for using human growth hormone. His ban was retroactive to Nov. 9, 2015, but that suspension will likely not prevent him from competing in Japan for Rizin.

Filipovic, 41, last competed at UFC Fight Night 64 in Krakow, Poland, where he earned a third-round technical knockout victory over Gabriel Gonzaga. “Cro Cop” has won four of his last five bouts and owns a 31-11-2 career mark overall.

Emelianenko, 39, last saw action in a June 17 victory over Fabio Maldonado, which was later overturned to a draw. The former Pride Fighting Championships heavyweight champion holds a career mark of 36-4 with 1 NC.