A mysterious #87 was working with the Oakland Raiders tight ends during this afternoon's practice.

Initially, the Raiders' public relations staff did not know the identity of #87, but Jerry McDonald of the Bay Area News Group reports that it's Eric Butler.

An undrafted free agent out of Mississippi State, the 6-2, 255-pound Butler has had stints with the New York Giants, Indianapolis Colts, and St. Louis Rams, but has yet to appear in an NFL game.

Butler caught one pass for 4 yards during the 2009 pre-season with the Rams, who waived Butler last Thursday.