Sean Cronin, in his second stint as a Marshall assistant coach, rejoined Coach Doc Holliday’s Herd staff in March 2013 as defensive ends coach. He also is a former graduate assistant on the MU staff.
Cronin, who spent the 2010 season as the defensive line coach at Marshall and has played on or coached for four national championship teams, was the defensive line coach at Temple in 2011-12. His return to the Herd – working in tandem with defensive tackles coach J.C. Price – has produced solid success in Marshall’s front four with a rotation system that enhances late-game and late-season play, not to mention depth and development.
With the Herd defense, Cronin also works closely with his father-in-law, veteran MU defensive coordinator and secondary coach Chuck Heater.
In 2015, as the Herd went 10-3 and won the St. Petersburg Bowl, Cronin guided two very productive ends in junior Gary Thompson -- at the “Fox” rush end spot -- and sophomore Ryan Bee. Thompson led the Herd in sacks (9) and tackles for loss (12.5), while Bee emerged from a third-team role in August camp to become not only a starter who produced 59 tackles with 4 sacks and 8.5 TFLs, but also was voted to the Conference USA All-Freshman Team.
The Herd, which has 100 quarterback sacks in Cronin’s three seasons on the staff, had an all-C-USA second team defensive end in 2014 in senior Arnold Blackmon, as Marshall won the league title and finished 13-1 and ranked in the national polls.
In 2013, Thompson was a C-USA All-Freshman pick, while starting defensive ends Alex Bazzie and Ra’Shawde Myers were all-conference honorable mention selections.
At Temple, led by three-time All-Mid-American Conference first team defensive end Adrian Robinson and All-MAC defensive end Morkeith Brown, the Owls defense dominated the league in 2011, leading in five categories while ranking No. 3 nationally in scoring defense. In 2012, Brown (Tampa Bay) and DE Adrian Robinson (Pittsburgh) signed rookie free agent contracts, helping to set the Temple school record with a class of 12 NFL signees.
Cronin first joined the Thundering Herd staff for Holliday’s debut season in 2010 after spending the 2009 season as the defensive line coach at The Citadel. Prior to The Citadel, Cronin spent three years as a graduate assistant defensive coach at Florida, working with eight NFL Draft picks.
He also worked with Holliday and Heater with the Gators.
Cronin won two national titles (2000 and ’01) as a player at Georgetown (Ky.) and helped Florida to BCS National Championships in his first and third seasons (2006, ’08) as a graduate assistant. Cronin went to UF after spending the 2005 season at Marshall, where he served as the offensive and special teams quality control assistant. In that role, Cronin performed multiple duties, including film breakdown and statistical analysis.
In 2002, Cronin earned his bachelor’s degree in history with a minor in coaching from Georgetown. In 2004, he completed his master's in rehabilitative science at Clarion (Pa.), where he spent two seasons as linebackers coach for the NCAA Division II program.
Cronin graduated from Moeller High School in Cincinnati and attended the University of Cincinnati, where he was a defensive end before transferring to Georgetown College, where he played defensive end his first season and defensive tackle during his final two years.
In 2002, he was an All-American and All-Conference selection. Upon graduation from Georgetown, Cronin spent the spring semester of his senior year interning at his alma mater assisting with the defensive line and in strength and conditioning efforts.
Cronin, 35, is married to the former Emily Heater. The couple, married May 16, 2009, has two daughters, Grace and Caitlin, and a son, Joseph.