Washington Redskins quarterback Robert Griffin III warms up before an NFL preseason football game against the Detroit Lions, Thursday, Aug. 20, 2015, in Landover, Md. (AP Photo/Mark Tenally)

Detroit Lions quarterback Matthew Stafford warms up before an NFL preseason football game against the Washington Redskins, Thursday, Aug. 20, 2015, in Landover, Md. (AP Photo/Alex Brandon)

Washington Redskins quarterback Robert Griffin III fumbles the ball as he's sacked by Detroit Lions defensive end Tyrunn Walker, top, and defensive end Ezekiel Ansah, right, during the first half of an NFL preseason football game, Thursday, Aug. 20, 2015, in Landover, Md. (AP Photo/Alex Brandon)

Washington Redskins wide receiver Andre Roberts (12) runs past Detroit Lions cornerback Nevin Lawson (24) during the first half of an NFL preseason football game in Landover, Md., Thursday, Aug. 20, 2015. (AP Photo/Alex Brandon)

Washington Redskins quarterback Robert Griffin III (10) passes the ball during the first half of an NFL preseason football game against the Detroit Lions in Landover, Md., Thursday, Aug. 20, 2015. (AP Photo/Mark Tenally)

Washington Redskins quarterback Robert Griffin III (10) runs onto the field before an NFL preseason football game against the Detroit Lions in Landover, Md., Thursday, Aug. 20, 2015. (AP Photo/Alex Brandon)

Washington Redskins quarterback Colt McCoy (16) is stopped on a short quarterback keeper by Detroit Lions linebacker Travis Lewis (50) during the first half of an NFL preseason football game, Thursday, Aug. 20, 2015, in Landover, Md. (AP Photo/Mark Tenally)

Detroit Lions running back Zack Zenner carries the ball into the end zone for a touchdown, dragging Washington Redskins linebacker Terrance Plummer (40) with him during the second half of an NFL preseason football game in Landover, Md., Thursday, Aug. 20, 2015. (AP Photo/Mark Tenally)

Washington Redskins wide receiver Reggie Bell (18) dives into the end zone past Detroit Lions strong safety Don Carey (26) for a touchdown during the second half of an NFL preseason football game in Landover, Md., Thursday, Aug. 20, 2015. (AP Photo/Mark Tenally)

Washington Redskins tight end Chase Dixon (83) is upended by Detroit Lions defensive back Brian Suite (45) during the second half of an NFL preseason football game, Thursday, Aug. 20, 2015, in Landover, Md. (AP Photo/Mark Tenally)

Washington Redskins wide receiver Rashad Ross (19) celebrates his touchdown with quarterback Kirk Cousins (8) during the second half of an NFL preseason football game against the Detroit Lions, Thursday, Aug. 20, 2015, in Landover, Md. (AP Photo/Alex Brandon)