Sam Bradford's knee 'better' but unclear when he'll return

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EDEN PRAIRIE, Minn. -- Vikings coach Mike Zimmer says Sam Bradford's left knee is "feeling better" a day after the quarterback missed Minnesota's game against Pittsburgh. But Zimmer is unsure when Bradford will play again.

Zimmer gave short and ornery answers Sunday when asked about Bradford following the loss to the Steelers. On Monday, he apologized for snapping and joked that there was no wine in the locker room after the difficult loss to help calm him.

Bradford's backup, Case Keenum, struggled while filling in. But Zimmer does not believe the Vikings need to find another quarterback while Bradford recovers. For now, Zimmer terms the injury day to day.