Updated

The Detroit Lions have acquired running back Ronnie Brown from the Philadelphia Eagles in exchange for running back Jerome Harrison and an undisclosed draft pick in 2013.

Detroit's starting running back, Jahvid Best, suffered his second concussion of the season in Sunday's 25-19 loss the 49ers, prompting the move for Brown.

Best will go through the NFL-mandated protocol for head injuries this week.

Brown, who signed a one-year contract with Philadelphia during the offseason, has rushed for 4,853 yards and 36 touchdowns in seven season with the Dolphins and Eagles.

Harrison played in eight games for the Eagles in 2010 after being acquired from the Browns. He has rushed for 1,681 yards and seven touchdowns in six season with the Browns, Eagles and Lions.