Johnson, 24, is a former second-round pick of the Lions back in 2018. He’s currently in the final year of his four-year, $6,503,698 rookie contract that included a $2,809,960 signing bonus.
Detroit waived Johnson earlier this summer and he was claimed by the Eagles. Philadelphia waived Johnson with an injury designation last week and he was released with an injury settlement.
The 49ers signed Johnson to their practice squad a few weeks ago.
In 2020, Johnson appeared in all 16 games for the Lions and rushed for 181 yards on 52 carries (3.5 YPC) to go along with 19 receptions for 187 yards receiving and three total touchdowns.