Breida (ankle) didn't participate in practice Thursday, Nick Wagoner of ESPN.com reports.
Injuries to Breida have taken their toll as the season has progressed. After averaging 12.8 touches for 99.5 scrimmage yards on 30.8 offensive snaps over the first four games, Breida has averaged 9.3, 45.7 and 15, respectively, in the last three. Currently, he's tending to an aggravation of a mid-ankle sprain, which hasn't allowed him to practice this week. Despite focusing on rehab, Breida is tough to rule out considering he's been active in every game in 2018. If he's limited or sidelined for the first time Sunday at Arizona, the 49ers will turn to Raheem Mostert and Alfred Morris to man the backfield.