It wasn't Pokemon Go that sent Mirko Cro Cop toward Rizin Fighting Federation. It was actually the UFC.

Cro Cop, the MMA legend, will be competing in an openweight tournament that begins on the Rizin card Sept. 25 in Tokyo, it was announced over the weekend. Cro Cop will not actually fight until Dec. 29, though, after being given a first-round bye.

When last we heard from the Croatian star, he was still under contract with the UFC, though suspended by USADA for two years. In a statement sent out Tuesday night, the UFC explained that it had terminated Cro Cop from the remaining fights on his deal after a request from the fighter, freeing him up to fight for Rizin.

Cro Cop, 41, was supposed to fight on a UFC card in South Korea last November. But the former PRIDE standout injured his shoulder, had to withdraw from the bout against Anthony Hamilton and subsequently announced his retirement.

It came out a few days afterward that Cro Cop had voluntarily informed USADA during a sample collection that he had used growth hormone to treat his shoulder injury. After an adjudication process, USADA ended up suspending Cro Cop for two years. He will not be eligible to return to the UFC's Octagon until Nov. 8, 2017.

"Former heavyweight contender Mirko Cro Cop announced his retirement from the sport of MMA in November, and recently requested that the remaining bouts in his promotional agreement with the UFC organization be terminated," the UFC said in a statement. "UFC agreed to terminate the remaining bouts in the promotional agreement, however, Cro Cop was advised that UFC does not have any power to reduce or terminate the sanctions imposed by the U.S. Anti-Doping Agency pursuant to the UFC Anti-Doping Policy."

Cro Cop will compete in the Rizin tournament along with fellow former PRIDE veteran Wanderlei Silva, who is still currently serving a suspension from the Nevada Athletic Commission (NAC) after evading a drug test in 2014. Silva has signed with Bellator MMA, but won't be able to fight again in the United States until May 2017.

Silva, too, was released by the UFC earlier this year after a legal battle with the company. Frank Mir, another aging legend facing a lengthy USADA drug suspension, also asked the UFC recently for a release if he ends up being banned for two years.