Last year, when Florida State running back Dalvin Cook fell out of the first round of the NFL draft, the Vikings made an aggressive trade to move up early in the second round to get him and install him as the heir apparent to future Hall of Famer Adrian Peterson.
Through the first four games, it looked like one of the best trades GM Rick Spielman ever made, as Cook started out with over 350 yards rushing in his a little over three and a half games. In his fourth game, though, he tore his ACL against Detroit, and was lost for the season.