Mere days ago, it seemed as if undrafted rookie running back Corey Kiner had an inside track toward securing a spot on the San Francisco 49ers' preliminary 53-man roster.
Now, Kiner is off the Niners roster.
Well, somewhat. After suffering a high-ankle sprain during San Francisco's preseason Week 2 victory over the Las Vegas Raiders, one that was expected to sideline him for at least a few weeks, the 49ers opted to waive/injured the former Cincinnati tailback despite impressive showings over the first two weeks of exhibition action.
Various team beat writers and reporters shared the transaction the Wednesday ahead of the Niners' preseason finale against the Los Angeles Chargers, including the San Francisco Chronicle's Eric Branch:
#49ers have waived/injured undrafted rookie RB Corey Kiner, who suffered a severe high ankle sprain Saturday .
— Eric Branch (@Eric_Branch) August 20, 2025
In addition to Kiner getting waived with an injury, the 49ers also released defensive lineman Demone Harris and signed offensive lineman Michael Dunn and wide receiver Malik Knowles, the latter two shoring up other positions that have dealt with severe injury attrition in recent weeks.
That's the hard lesson for Kiner.
The Niners have been hit so hard with preseason injuries that fringe players whom they'd likely prefer to keep on the 90-man pre-Week 1 roster aren't sustainable, namely when so many other positions are shorthanded. The running back room, which also lost Patrick Taylor Jr. for the year in the same game, is low on bodies. So is the offensive line after right guard Dominick Puni's knee injury.
Tack on a seemingly endless revolving door at wide receiver because of injuries there, and it makes sense why Kiner had to be expendable despite averaging 5.7 yards per carry over the preseason.
Corey Kiner's future with 49ers isn't sealed... yet
Waiving/injured Kiner freed up a desperately needed roster spot right away, but it doesn't automatically signal the end of the rookie's tenure in the Bay Area.
Should Kiner clear waivers, he'd revert to San Francisco's injured reserve list the following day, as are the NFL rules regarding injury lists. And, as head coach Kyle Shanahan described during Tuesday's press conference, the running back's injury was "a pretty bad one."
This might discourage the 31 other teams across the league from putting in a claim on Kiner, thereby using up a valuable roster spot on someone who won't be available for some time.
Not saying it never happens (just ask the 49ers how things went down with veteran cornerback D.J. Reed), but it's rare for teams to claim injured players.
So, the probability of Kiner ending up on IR after clearing waivers is awfully strong, meaning he's not on the roster in that regard but still very much part of the squad, albeit on an injury list.
It's a tough reality for the promising first-year pro to accept, but it was a necessary one for an injury-plagued Niners team to implement.