OWINGS MILLS, Md. — In the midst of one of the most frustrating seasons in franchise history, the Ravens revealed Monday that their longest-tenured assistant coach has been battling something far more serious than anything transpiring on the football field. Longtime defensive line coach Clarence Brooks, 65, has been receiving treatment three times per week for esophageal cancer, a diagnosis he received earlier this season. Because of those weekly radiation and chemotherapy sessions, Brooks did not accompany the team for either of its Monday night games this season. He will undergo surgery to remove a tumor from his esophagus in January or February. “It just puts it in perspective once again — the things that are important,” head coach John Harbaugh said. “I say all the time, ‘Football is a metaphor for life.’ The challenges that you face are similar to what people face in life, but there are people out there facing things that are just adversity, challenging, demanding, difficult things that they’re facing [that] this brings close to our home through Clarence. “Maybe a season like this gives you a chance to think about some things as a coach or as players, things that are going to stick
