Horse-collar tackle

The horse-collar tackle is an American football maneuver in which a defender tackles another player by grabbing the back collar or the back-inside of an opponent's shoulder pads and pulling the ball carrier directly downward in order to pull his feet from underneath him. The technique is most closely associated with Pro Bowl safety Roy Williams. This kind of tackle was banned from the NFL during the 2005 off-season. The rule forbidding it is often referred to in the press as "The Roy Williams Rule". The rule, with modifications, was adopted in college football in 2008 and high school football in 2009.

The horse-collar tackle rose to infamy during the 2004 NFL season, in which it was implicated in six major injuries, four of which were caused by Williams, including two in one game. The injuries that season included broken legs for Philadelphia Eagles wide receiver Terrell Owens, Eagles quarterback Donovan McNabb, Carolina Panthers wide receiver Steve Smith Sr., Baltimore Ravens running back Musa Smith, and Tennessee Titans wide out Tyrone Calico. On May 23, 2005, NFL owners voted 27–5 to ban the tackle, with the Dallas Cowboys, Detroit Lions, New England Patriots, New Orleans Saints, and San Francisco 49ers voting against. The first year of the ban, only two penalties were called by referees for the horse-collar tackle. Owners voted 25–7 in 2006 to expand the rule to include tackles by the back of the jersey in addition to tackles by the shoulder pads.

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