Sam Shields waging comeback with Rams, in spite of concussion history

THOUSAND OAKS — For months, as his head throbbed with pain and his eyes struggled with bright lights, Sam Shields worried his once-promising NFL career might be over.
In 2015, Shields was the Green Bay Packers’ top cornerback, ranking among the league’s best at the position. But in December of that season, his helmet slammed into the turf, and Shields blacked out. Diagnosed with a concussion, the Packers shelved him for the remainder of the season. He returned in time for the 2