Thomas spent two years at Dubuque earning his Master's degree where he took the team to its first-ever NCAA Tournament appearance. During his time at Dubuque as the defensive coordinator, he helped lead the defense to the best defensive season in program history. They finished tenth in NCAA DIII in scoring defense, allowing 7.75 goals per game, fourth in caused turnovers per game (15.85) and 33rd in ground balls with 719. Thomas also coached four defensive all-conference players, the conference defensive player of the year, the conference rookie of the year, multiple academic all-conference players and a NCAA statistical leader in caused turnovers in a season. Prior to that, he was the head boys varsity lacrosse coach at Geneva High School.