Coleman is the third 49er injured in last week's victory against the New York Jets to go on injured reserve, joining defensive end Nick Bosa and defensive tackle Solomon Thomas with that designation. Unlike Bosa and Thomas, both of whom are out for the season with torn left ACLs, Coleman is expected to return this season.
San Francisco coach Kyle Shanahan hinted that a move to injured reserve for Coleman could be coming on Wednesday, noting that Coleman's knee sprain was more serious than starting running back Raheem Mostert's.
Under new league rules for players on injured reserve, Coleman is eligible to return for the team's Oct. 18 game against the Los Angeles Rams, although the following week against the New England Patriots might be more realistic.
"I'm expecting Tevin to be out a little bit," Shanahan said. "I'm expecting about four weeks, so he could be a possibly IR candidate here to return towards the end of the week. He's worse than Raheem is."
Through the first two weeks, Coleman had worked as the primary backup to Mostert, rushing for 30 yards on 18 carries with three catches for 34 yards. Mostert has been ruled out this week because of his own knee sprain but is considered week-to-week.
The 49ers filled Coleman's spot on the roster by promoting center Hroniss Grasu from the practice squad. Grasu had been a practice squad activation each of the past two weeks.
Additionally, the Niners activated running back JaMycal Hasty and linebacker Joe Walker for Sunday's game against the New York Giants using their two practice squad spots for the week. Hasty is expected to work as the team's third running back behind Jerick McKinnon and Jeff Wilson Jr., while Walker provides some additional depth with linebacker Dre Greenlaw out this week because of a thigh injury.
In addition to Coleman, Mostert and Greenlaw, the Niners will be missing tight end George Kittle (knee), quarterback Jimmy Garoppolo (ankle) and defensive end Dee Ford (back) against the Giants. They're also awaiting the returns of cornerback Richard Sherman (calf) and receiver Deebo Samuel (foot), both of whom are on short-term injured reserve.