Matthew Riddle, who signed with Bellator MMA after being released by the UFC, has announced his retirement.

Riddle, scheduled to fight next week, suffered a cracked rib in training and now plans to move on with his career.

“I’m retiring from MMA,” Riddle posted on Twitter, “I cracked my rib and I can’t fight Sept 20th (at Bellator 100) can’t give me a fight this year so I can’t afford it.”

Riddle, 27 years old, fought for the UFC 12 times after competing on The Ultimate Fighter 7. He picked up wins in his last four fights initially before failed drug tests took away two of the wins. He was released after his fight with Che Mills in February.