According to MMAWeekly, Mauricio 'Shogun" Rua has agreed to fight Lyoto Machida. No date has been made for the fight, and Lyoto Machida's camp has yet to confirm or deny if the agreement is true or false. We do know that the UFC is pushing to make this fight happen, and Shogun vs. Machida is likely going to happen instead of Rampage vs. Machida:

Mauricio "Shogun" Rua has in principle accepted a bout with new light heavyweight champion Lyoto Machida, MMAWeekly.com has learned from sources close to negotiations.

Though a concrete date for the fight could not be confirmed, and Machida’s management could not be reached at the time of this writing, sources say it would likely take place in October or November.

It sounds like minor details are the only thing in the way at this point, and this fight will likely take place in October or November. The matchup will set up a Machida vs. Shogun title bout with Rampage vs. Evans taking place in December. The outcomes of the bouts will likely determine the future matchups between the four fighters. Alternatively, the UFC could decide to mix in some other talent such as Luiz Cane moving up in the ranks or potentially the return of Tito Ortiz as some fans have suggested.

Shogun vs. Rampage is a very likely outcome at some point in this scenario, and the UFC could pump the rematch up with the marketing department. Rampage vs. Evans should have some fantastic buildup from the reality series, and Shogun vs. Machida should be an interesting test for Shogun Rua, who has only recently began to look a bit like his former self. Get ready for some heavy action in the Light Heavyweight division come late in the year.

UPDATE: From MMAMania.com via SuperLutas.com.br

The 2005 Pride FC Middleweight Grand Prix winner, Mauricio "Shogun" Rua, earlier this week did indeed sign a bout agreement to challenge UFC Light Heavyweight Champion Lyoto Machida, which will more than likely take place at UFC 104 from the Staples Center in Los Angeles, Calif., on Oct. 24.

SuperLutas.com.br was able to confirm the rumored match up with sources close to the Brazilian’s camp.

Bout agreement signed makes this all but confirmed by the UFC.