Alonso suffered the injury in the second quarter and was able to walk back to the locker room. Rookie Jordan Hicks replaced Alonso at linebacker.
The Eagles traded for Alonso over the off-season, acquiring him in a trade that sent away running back LeSean McCoy.
Alonso was a second-round pick of the Buffalo Bills in 2013. He won Rookie of the Year after his first season, but missed all of 2014 with a torn ACL in the same knee he injured Sunday.
In his first year, Alonso recorded 159 combined tackles, with one forced fumble and four interceptions.
– Rohan Nadkarni