The Detroit Lions today placed running back Kerryon Johnson on injured reserve after undergoing knee surgery. Johnson injured his knee in the first half of this past Sunday's loss to the Minnesota Vikings. He would be eligible to return in the season's 15th game. Johnson ran for 641 yards last season before missing the last six games with a knee injury. Also the Lions Tuesday traded starting safety Quandre Diggs to the Seattle Seahwks. Draft picks were exchanged in the deal as well. The Lions, 2-3-1 , host the New York Giants Sunday.