Fedor Emelianenko will meet Dan Henderson on July 30 on a Strikeforce card in the Chicago area, a source with knowledge of the fight confirmed to ESPN.com Tuesday.

The bout pitting two of mixed martial arts' most revered competitors, which is set to air not on pay-per-view as had been discussed but on Showtime, marks the first time Emelianenko's promoter, M-1 Global, and Zuffa, which purchased Strikeforce in March and has operated the UFC since 2000, would join forces for an event.

Details are still taking shape but sources said that the fight has been agreed to in principle and should be finalized within a few days.

Henderson expressed interest in challenging Emelianenko after the 40-year-old American captured Strikeforce's light heavyweight title against Rafiel "Feijao" Cavalcante on March 5. Last month a representative for Emelianenko informed ESPN.com that the 34-year-old Russian told his camp he would agree to fight Henderson.

Questions over the bout's contracted weight limit were laid to rest when Henderson (27-8), who campaigned the majority of his career at 185 and 205 pounds, said a cap in the neighborhood of 220 pounds wasn't necessary against a man who ranked as MMA's top heavyweight from 2003 through 2010.

Coming off consecutive losses for the first time in his career, Emelianenko (31-3) was working to slim down anyhow, according to sources in his camp. In his last appearance in the cage, a technical-knockout setback against Antonio Silva in February, the Russian appeared softer than usual around his midsection. He has since traveled to the Netherlands, where he worked on his fitness and technical striking skills. He is scheduled to do so again prior to meeting Henderson.

Based on the terms of Henderson's contract, the former two-division Pride champion is owed a fight by the end of July or Strikeforce would be in violation their agreement.

Josh Gross covers mixed martial arts for ESPN.com