In American football and Canadian football, a sack occurs when the quarterback is tackled behind the line of scrimmage before he can throw a forward pass, or when the quarterback is tackled behind the line of scrimmage in the "pocket" and the intent of what he was going to do is unclear. This often occurs if the opposing team's defensive line, linebackers or defensive backs are able to quickly get past blocking players of the offensive team (the quarterback's protection), or if the quarterback is unable to find a back to hand the ball off to or an available eligible receiver (including wide receivers, running backs and tight ends) to catch the ball, allowing the defense a longer opportunity to tackle the quarterback.

In the NFL, it is possible to record a sack for zero yards. The QB must pass the statistical line of scrimmage to avoid the sack. A sack is also credited when a defender causes the quarterback to fumble and the defending team recovers the ball behind or at the line of scrimmage.

Elvis Kool Dumervil (born January 19, 1984) is an American football defensive end for the Denver Broncos of the National Football League (NFL). He was drafted by the Broncos in the 2006 NFL Draft in the 4th round. He played college football at Louisville.

Dumervil's parents were Haitian immigrants to Miami's Little Haiti neighborhood. Separated when Dumervil was 3, they raised a total of 10 children. Rated among the top 25 defensive ends by most publications, Dumervil had a Miami Jackson High School record 78 career sacks.

His college career began slowly as a modest contributor during his first two seasons at the University of Louisville; he tallied just 28 tackles and two sacks. John L. Smith's staff had planned on redshirting him during the 2002 season, but injuries to other players and a lackluster performance by the defensive line forced him into the rotation.

He emerged during the 2004 season as a junior, recording 10 sacks and 11 tackles for a loss. His 2005 season was one of the best for a defensive end in both NCAA and school history, when he broke the NCAA single-game sack record (6) in a game against the rival Kentucky Wildcats, and broke the NCAA record for forced fumbles. His sack total also broke the Big East record set by Dwight Freeney, who was a player that Elvis desired to emulate. He won several awards for the 2005 season, including the Bronko Nagurski Trophy, the Ted Hendricks Award, and Big East player of the year, and was recognized as a consensus first-team All-American.

Thomas Edward Patrick "Tom" Brady, Jr. (born August 3, 1977) is an American football quarterback for the New England Patriots of the National Football League (NFL). After playing college football at Michigan, Brady was drafted by the Patriots in the sixth round of the 2000 NFL Draft.

In Brady's ten seasons as a starter, the Patriots have earned trips to the Super Bowl in half of them (XXXVI, XXXVIII, XXXIX, XLII, and XLVI), winning three of them (XXXVI, XXXVIII, and XXXIX). He has also won two Super Bowl MVP awards (XXXVI and XXXVIII), has been selected to seven Pro Bowls (and invited to eight, although he declined the 2006 invitation), and holds the NFL record for most touchdown passes in a single regular season. His career postseason record is 16–5. He also helped set the record for the longest consecutive win streak in NFL history with 21 straight wins over two seasons (2003–04), and in 2007 he led the Patriots to the first undefeated regular season since the institution of the 16-game schedule. Brady has the fourth-highest career passer rating of all time (96.4) among quarterbacks with at least 1,500 career passing attempts.

Sean Patrick Lee (born July 22, 1986) is an American football linebacker for the Dallas Cowboys. He played college football at Penn State.

He is the son of Craig Lee and Geralyn Lee of Upper St. Clair, Pennsylvania. Lee's older brother Conor was the placekicker for the University of Pittsburgh and his sister Alexandra was a student athlete at Upper St. Clair High School. Sean is also a grandson of Federal Judge Donald J. Lee of the United States District Court for the Western District of Pennsylvania.

Lee was a multi-sport star at Upper St. Clair High School outside Pittsburgh, he was a three-year starter at point guard in basketball, averaging 21.2 points, 9.1 rebounds and 3.2 assists as a senior, and winning a district title. In football, Lee rushed for 1,240 yards and 21 touchdowns while registering 95 tackles and four picks as a safety for an 11-1 squad his senior year.

A 2005 graduate of Upper St. Clair High School in Upper St. Clair Township, Pennsylvania. Lee went on to play college football at Penn State. Heading into 2008, Lee was a starting outside linebacker for coach Joe Paterno's Nittany Lions for two consecutive seasons. In his junior year he was 2nd team all Big Ten, finishing second on the team in tackles with 138. He had a season high 17 tackles versus Illinois, and registered more than 10 tackles in all but three games. He also had two interceptions and three forced fumbles on the season.

Matthew Clayton Flynn (born June 20, 1985) is an American football quarterback for the Seattle Seahawks of the National Football League (NFL). He was drafted by the Green Bay Packers in the seventh round of the 2008 NFL Draft. He played college football at LSU.

Matt Flynn attended Robert E. Lee High School in Tyler, Texas, where he was coached by Mike Owens, and was teammates with Justin Warren, Brandon Pettigrew, and Ciron Black. Flynn was one of the top-rated quarterbacks in the state of Texas, alongside Drew Tate of Baytown, Texas. As a junior in 2001, Flynn guided his team to a 5A playoff appearance but lost to the eventual state champion Mesquite High School. Flynn completed 101 of 199 passes for 1,650 yards, 13 touchdowns and 9 interceptions for the season. As a senior, he completed 124 of 206 passes for 1,679 yards and 9 touchdowns. He also displayed his ability on the ground with 305 yards rushing and 12 touchdowns. Flynn displayed toughness by leading Robert E. Lee High School to a semifinal appearance in one of the toughest classifications in Texas despite playing his last four games with a broken foot. His team lost to Midland High School 24-14.