An undisclosed injury has forced Dennis Siver off of June 4’s UFC 199 card at The Forum in Inglewood, California, according to a report from BJPenn.com.

Ultimate Fighting Championship officials are searching for a new opponent to face Penn, the report stated.

Penn, 37, is looking to return following a near two-year hiatus. The former two-division UFC champion has dropped his last three bouts to the likes of Nick Diaz, Rory MacDonald and Frankie Edgar.

Silver, also 37, was looking to put an end to a losing streak. The German-based featherweight has dropped his last two contests.