The Browns' win on Thursday night came with a cost -- their star receiver, Elijah Moore, suffered a terrifying head injury that sent him into convulsions right on the turf.
The scary moment happened just before halftime of Cleveland's "Thursday Night Football" tilt with the New York Jets ... when Moore slammed his head face-first into the grass at Cleveland Browns Stadium after making a big catch.
Replays of Moore's grab showed he wasn't able to brace himself as a Jets defender flung him to the ground -- and almost immediately, he appeared to be knocked out.