He played linebacker for eight seasons in the National Football League (NFL) for the Buffalo Bills, the San Diego Chargers, and the Atlanta Falcons.
Despite knee injuries lowering high draft expectations and ending Butkus Award speculation, Holecek finished his Illini career with over 430 tackles.
Coach Holecek announced his Loyola Academy retirement in December 2022 (with a cumulative 185-36 record), planning to focus "on the next chapter of his career”.
[1] Holecek was a three-sport athlete at Marian Catholic High School in Chicago Heights, Illinois, excelling in wrestling, baseball, and football.
Holecek was selected to a Chicago all-star baseball team that toured Europe his junior summer, but he decided to play football after receiving multiple Big Ten and division one scholarship offers.
Holecek finished his high school career with 243 tackles, 13 sacks, two fumble recoveries, three interceptions, two punts blocked, 16 receptions and 2 TD passes.
Other retired Marian jerseys include Mike Prior and high school and one-season NFL teammate Rodney Harrison (San Diego Chargers).
The Foursome also featured All-American and first-round, second and third overall draft picks, Simeon Rice and Kevin Hardy, as well as, Butkus award winner Dana Howard.
Holecek's arm-wrestling match with his childhood hero, legendary Walter Payton, was stated to be one of his greatest college football-related moments.
"I remember Holecek was named the Big Ten Defensive Player of the Week" (November 1993 comeback win vs Minnesota) Tepper said of the least heralded of his all-star linebacker corps.
"We had two future Butkus Award winners (Howard and Hardy) and Simeon Rice, who was just as good or better than two others I coached — Khalil Mack and Bruce Smith.
He also briefly played middle linebacker in a 4-3 alignment when injuries caused Coach Phillips to switch defenses mid-season.
John emerged as a defensive stalwart and on-field coach for the Bills, notching an incredible 414 tackles from 1998 to 2000 and became known for his technique and football acumen.
In 1998 Holecek led the Bills with 133 tackles in his first season as a full-time starter and was named the team's recipient of the Ed Block Courage Award.
In 1999 Holecek tallied 116 combined tackles, including 63 unassisted, to go along with one sack, one interception, six passes defensed and two forced fumbles.
In his seventh season, Holecek was released very late in training camp in salary cap move by a new Bills head coach and GM.
After retiring from the NFL, Holecek returned to Illinois to work in finance and assist coaching high school football at St. Ignatius in Chicago.
NFL coaches Marv Levy and Wade Phillips called the school's AD Pat Mahoney on Holecek's behalf.
In 2011, he coached the Ramblers to a second-place finish in the Class 8A State Championship, losing to Bolingbrook High School 21–17 in inclement weather.
In April 2014, Holecek's coaching mentor Marv Levy visited Loyola as part of the NFL "Heart of a Hall of Famer" program.
Levy's lessons were laced with words like “perseverance”, “work ethic”, and “preparation”, hallmarks of Holecek's playing career and coaching tenure at Loyola.
Loyola won the 2015 Chicago Catholic League Blue conference title after a 49–21 victory over defending 7A State Champion Mt.
LA defeated Marist 41–0 (with a running clock imposed) to win the IHSA class 8A State Championship, extending its season record to 14–0.
Loyola players were paid a visit by NFL legend Marv Levy prior to the beginning the 2016 8A IHSA playoffs (#1 seed).
Loyola finished the regular season at 8–1 in 2017 and the Ramblers’ won their third consecutive undefeated and outright Catholic Blue League title in a row (with Holecek again receiving Coach of the Year awards).
LA's home win streak stood at 29 games (including a victory against perennial Californian powerhouse Bishop Amat) as the playoffs began.
Underdogs Loyola beat the 14th, 6th (10-1 Maine South), 3rd (undefeated Oswego), 2nd (12-0 and reigning 8a champion Lincoln Way East) and 1st seeds (13-0 Brother Rice) during their playoff run.
NFL Defensive Player of the Week, for a stellar Monday Night Football game vs the Miami Dolphins in October 1999.
Other inductees in his class included Jim Calhoun, Bobby Hull, Glenn Doc Rivers, Barry Sanders and former Notre Dame and Pittsburgh Steelers running back Rocky Bleier.
Holecek's Loyola Academy teams volunteer and visit Misericordia, often playing pick-up games with children and adults with developmental disabilities.