Former UFC welterweight champion Georges St-Pierre, who is in the midst of a sabbatical from fighting, announced on his Facebook page Thursday that he tore the anterior cruciate ligament in his left knee this week and will require surgery.
He tore the ACL in his right knee in 2011 and missed about a year.
St-Pierre wrote, "Just got confirmation that I tore my left knee AC during training this week. ... Surgery in a few days and rehab starts right away. We all face challenges in our lives and I know only one way to take this one: Pain, hard work, no shortcuts and I will soon be back at 100%"
UFC president Dana White has said he is certain St-Pierre would return to competition, but if he does, it's going to be much longer than originally anticipated.