After playing 19 snaps (63 percent) of special teams on Sunday, linebacker Ben Niemann was removed from the game with what we were told was a hamstring injury. This was confirmed on Monday. While we do not know the severity and exact specifics of the injury, it was announced that he was not going to practice Wednesday.
These injuries can be especially debilitating to players who play very actively on special teams given the demands of what they must do. In some respects, it is even harder to play special teams with a hamstring injury due to the amount of sprinting and cutting that must be done.
Given the high workload in the final preseason game that this player had (26 on defense or 41 percent of snaps, and 16 on special teams, or 53 percent of snaps), this is likely the most activity he has had in quite a while in this short of a span. Also factor in the heat that was present in LA on Sunday and now you are adding in dehydration as a possibility, which only aides in muscle injuries.
Not knowing the extent of the actual injury, it is reckless to put out predictions on return to play. Hamstrings can be difficult because you want to make sure that the player is good to go before returning as to avoid re-injury or chronic symptoms.
When he returns to practice, you can probably be certain he feels as if he can contribute and is ready to play full speed again.