Deep in the fourth quarter, with the Seahawks’ lead seemingly insurmountable, Williams snagged a Justin Herbert pass in the middle of the field. As he turned toward the first-down marker, he was brought down and landed awkwardly on his lower right leg.

Williams struggled to put weight on his right leg. He had to be helped off the field.

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Williams was initially ruled as questionable, but he did not return.

After the game, Williams continued having difficulty putting weight on his leg, per Daniel Popper of The Athletic.

How long will Mike Williams be out?

The team didn’t immediately reveal how severe Wiliams’ injury was, but given the brutal nature of the tackle — Williams’ lower leg seemed to give a lot as he went down — it wouldn’t be surprising to see the six-year pro be out for a prolonged period.

Williams’ injury adds to the Chargers’ woes on offense. Between Williams and Keenan Allen (hamstring), Herbert hasn’t had his full complement of weapons lately.

Chargers WR depth chart

With Williams potentially headed for a lengthy spell of time on the sidelines, Herbert’s supporting cast continues to get weaker and weaker. Here’s how the Chargers’ wide receiver depth chart shapes up in light of Williams’ absence.