Professional wrestler Brock Lesnar announced Tuesday that he signed a new contract with World Wrestling Entertainment and would not consider a return to the UFC to restart his career in mixed martial arts. The 37-year-old made his decision despite a last-minute offer from UFC Chairman Lorenzo Fertitta to double his compensation.

Rumors had swirled for months that Lesnar, a former UFC heavyweight champion, would return to mixed martial arts once his WWE contract expired after WrestleMania 31 takes place Sunday, March 29. Lesnar last competed in the UFC in 2011, but there was mutual interest in a new deal this year and he trained as recently as last week for a possible return, according to the Associated Press. But a lucrative three-year offer from the WWE convinced Lesnar to stay put.

“Lorenzo said to me, ‘can we sharpen your pencil? Can we double it?’” Lesnar told the AP. “I said, ‘it’s not about that. I’m calling you to tell you where my heart is, and it’s not about the money. …And then, in the back of my mind, I’m thinking, ‘Well, yeah, it is about the money, but I don’t have to beat myself up for it.’”

Lesnar first announced his decision during an appearance Tuesday on ESPN’s “SportsCenter.” He said training for a potential return had gone well, but that he lacked the desire to compete again as a professional fighter.

“It was a hard decision to make. It took me a year. I’ve thought about this for a year. At the end of the day, it’s all about me wanting to have fun. The last two-and-a-half months I’ve been training to get back into the Octagon. I felt physically great, but something lacked mentally – and that’s not good,” he said.

Speculation about Lesnar’s possible MMA return reached its height in December, when a report by Wrestling Observer Newsletter said WWE officials had all but given up on the possibility that he would resign. Neither Lesnar nor UFC President Dana White directly addressed the rumors at the time.

Lesnar lost his UFC debut in 2008 in a fight against former heavyweight champion Frank Mir, but rallied to win his next four professional fights. He scored a dominant victory over UFC legend Randy Couture to win the UFC heavyweight championship and went on to defend his title twice. But a string of health problems, including a near-fatal bout with diverticulitis, derailed Lesnar’s mixed martial arts career. After back-to-back losses, he retired from the sport in 2011 and shortly thereafter re-signed with the WWE.