Johnston (lower body) brought in one of two targets for a 65-yard touchdown in the Chargers' 20-18 preseason loss to the Rams on Thursday.
The speedy fourth-year pro recently missed some practice time due to a lower-body injury he suffered during a joint practice with the 49ers leading up to Los Angeles' second preseason game, yet Johnston looked at full health when blowing past the Rams' secondary for a 65-yard touchdown with just under 10 minutes remaining in the first quarter. Thursday's snaps were Johnston's only action this preseason, but he looks prepared to reprise the No. 2 receiver role that's netted over 700 receiving yards in each of the last two seasons beginning with a Week 1 home matchup against the Cardinals.