Colorado sophomore quarterback Tyler Hansen has broken the right thumb on his throwing hand in the Buffaloes' annual spring game.
Hansen was injured when he slammed his thumb into the helmet of defensive end Marquez Herrod during the game Saturday in Boulder, Colo.
Team spokesman David Plati said Hansen was scheduled for surgery at Boulder Community Hospital and is expected to be out until mid-June.
Hansen split snaps last season with junior quarterback Cody Hawkins.
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