Vikings sign Ryan D'Imperio to active roster, waive Allen Reisner
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After four games, the Minnesota Vikings apparently have decided they need a fullback on the roster.
Veteran tight end Jimmy Kleinsasser had held up relatively well while taking the vast majority of "F" snaps since the Vikings cut D'Imperio and rookie Matt Asiata in the final roster reduction a month ago.
But playing Kleinsasser as a fullback takes one of the Vikings' best inline blockers off the line of scrimmage, and Adrian Peterson's efficiency had declined each week, from 6.1 yards per carry in the opener at San Diego to 3.5 yards per carry in Sunday's loss at Kansas City.
D'Imperio, 24, was a seventh-round pick in 2010. He spent last season on the practice squad, then entered training camp this year as the starting fullback before struggling much of the preseason.