A broken hand will prevent Tim Sylvia from making an Oct. 25 debut with the Dream promotion in Japan, said the fighter’s manager Monte Cox.

Cox said the 6-foot-8 Sylvia broke his right hand about a minute and a half into his heavyweight bout with Jason Riley at Adrenaline 4 last Friday in Council Bluffs, Iowa. Sylvia scored a technical knockout 2:32 into the first round. Cox said the 33-year-old Sylvia will be out of action until December.

Sylvia, a former UFC heavyweight champion, had struggled in recent bouts against No. 1 heavyweight Fedor Emelianenko, who choked him out in 36 seconds, and aging boxer Ray Mercer, who dropped Sylvia in nine seconds at Adrenaline 3 last June.

Strikeforce heavyweight champion Alistair Overeem was one of the names floated for Sylvia’s Oct. 25 debut, and Cox said he hopes to get that bout or another of equal proportion on track for the promotion’s planned New Year’s Eve event.

“We were really happy to get the call from Japan and we were seriously considering if we could be ready for a big fight that quickly,” said Cox. “However, the broken hand made the decision for us. Hopefully, we can get that big fight on New Year’s Eve.”

Overeem’s opponent for his rumored Oct. 25 appearance in Dream has not been named. The Dutchman has already been scheduled to face Peter Aerts in K-1’s World Grand Prix “Final 16” on Sept. 26, and could return for the tournament’s finals December in Japan. Overeem has yet to defend his Strikeforce title since winning it in November 2007.

Cox said he’s been in talks with rival promotion Sengoku for Sylvia’s services as well.