Watch Now: Recap: 49ers at Colts (1:38)

The San Francisco 49ers got some more bad injury-related news on Saturday. 

Already down their No. 1 and No. 2 running backs, the 49ers saw starting linebacker Reuben Foster exit their third preseason game, against the Indianapolis Colts. Foster was later diagnosed with a concussion, and the team quickly ruled him out for the remainder of the game. 

Foster had recorded two tackles, one for loss, before sustaining the injury. 

He had himself an eventful offseason, getting suspended two games by the NFL due to weapons and drug-related charges. In January, Alabama police charged him with misdemeanor possession of marijuana, but the case was dismissed in May. In July, Foster pleaded no contest to misdemeanor weapons possession and was sentenced to two years probation, 232 hours of community service, and $235 in fines. He had previously had domestic violence charges dismissed in May. The 49ers stated that his suspension was unrelated to the domestic violence inquiry. 

"I accept the League's decision and am sorry that my mistakes have hurt my team," Foster said in a statement at the time the suspension was handed down. "I have a responsibility to the 49ers, our fans and our community, and I am committed to learning from this situation and making better choices in the future. The support I have received over the last five months has been humbling, and I do not take it for granted."

Foster was taken with the No. 31 overall pick in 2017. He appeared in 10 games during his rookie season, racking up 59 solo tackles and quickly becoming a strong presence in the middle of the San Francisco defense. If he has to miss time due to injury in addition to his suspension, that would be bad news for a 49ers team that has designs on taking a big step forward this season.