Mike Williams might need back surgery on his herniated disk that would rule him out for the entire 2017 season.
Williams was the seventh overall pick by the Los Angeles Chargers.
The team still is hoping that Williams will respond positively to the second epidural, but also knows there's a real chance he will not and his rookie year will be over before it begins.
"This may be a lot more serious than people thought," said one source familiar with the injury.
The Chargers remain uncertain about when Williams initially injured his back, but one source said it's possible it was injured at the combine and during his pro day, but he did a good enough job masking it so that teams would not know and his draft stock would not be impacted.