This term refers to when a defensive lineman lines up across from the offensive line. A "three-technique" DT is positioned on the outside shoulder of the guard to generate a pass rush in a 4-3 defensive front.
A "five-technique" guy is someone who's better suited to play defensive end in a 3-4 scheme. He'll line up to the outside shoulder of the offensive tackle and is responsible for filling the gaps on running plays.
Defensive line prospects aren't necessarily designated as three- or five-technique players on draft day; it's more of a projection by scouts and analysts as to where a player will fit best. With teams creating more looks and alignments for their defensive fronts beyond their base packages, players need to be versatile enough to handle a variety of techniques.
Examples of "Three-Technique" Players: Geno Atkins, DT, Cincinnati Bengals (120th overall, 2010 NFL Draft); Sylvester Williams, DT, North Carolina (2013 prospect, pictured above)
Examples of "Five-Technique" Players: J.J. Watt, DE, Houston Texans (11th overall, 2011 NFL Draft); Margus Hunt, DE, Southern Methodist University (2013 prospect)
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