Steelers WR Diontae Johnson exits with hamstring injury

PITTSBURGH -- Diontae Johnson's season-opener ended early after the Pittsburgh Steelers wide receiver sustained a hamstring injury in the third quarter.

After making his biggest play of the day -- a 26-yard reception -- Johnson appeared to go down awkwardly. He had to be helped off and went back to the locker room after a short evaluation in the injury tent. Johnson picked up 21.5 yards after the catch, per NFL Next Gen Stats, good for the Steelers' longest play of the day in an offensively stagnant outing against one of the NFL's best defenses in the San Francisco 49ers.

Johnson finished with three catches on six targets for 48 yards.

Johnson also slipped on the field in the first quarter as…