49ers' CJ West: Hyperextends knee

West has a hyperextended knee, David Lombardi of the San Francisco Standard reports.

West's likely looking at a short-term injury, per Lombardi, though a more specific recovery timeline hasn't been established for the rookie fourth-round pick. The 49ers begin regular-season play Sept. 7 against the Seahawks. San Francisco's next preseason game is Saturday against the Raiders.