Matt Cassel is taking over at quarterback for Dallas after Brandon Weeden lost all three of his starts in place of the injured Tony Romo.
Coach Jason Garrett said Wednesday he made the move "to see if we can get our offense going a little bit more."
The Cowboys (2-3) are on their bye and have about a week and a half to get Cassel ready to face the NFC East-leading New York Giants on Oct. 25.
In Cassel, Dallas is picking someone with more experience -- and more wins. Cassel made 71 starts for New England, Kansas City and Minnesota and has 33 wins to just five for Weeden, although both have losing records for their careers.
The Dallas offense has posed little threat down the field with Weeden.