According to Matt Barrows of the Sacramento Bee, Bush slipped on the track adjacent to a sideline wall and seemed to slide into it.
Doctors looked at Bush's left leg following the play. Bush was carted off of the field.
The play was followed by a skirmish between the two teams. There were three penalties on the 49ers, including unsportsmanlike conduct for a coach on the sideline.
The injury prone Bush missed a number of games earlier this season with a calf injury. With Carlos Hyde inactive, Mike Davis and Kendall Gaskins are the only remaining running backs for the 49ers. Yesterday, the 49ers waived RB Jarryd Hayne in order to activate Gaskins.
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