Coach Dunnigan played football in Peoria Illinois under head coach Jim Donahue at Woodruff High School, where he lettered in football and played Quarterback for four years graduating in 2004. After graduating, Marcus began coaching football at the youth level while attending Illinois Central College, where he studied Physical Education. In 2006 Marcus signed to play Minor League arena football as a Quarterback, where he was voted an all-star in 2007 and 2008. In his last season in 2010, he passed for 1,100 yards and 10 touchdowns.  After years at the youth level, coach Dunnigan began his coaching career at the high school level in 2015, joining the staff at Brebeuf Jesuit Preparatory High School in Indianapolis, IN, as Quarterback Coach. He helped guide an offense that averaged 35 ppg, before relocating to Louisville, KY and joining the staff at Waggener High School as Wide Receivers & Defensive Backs coach in 2017-18. In 2019 he joined the staff at Eastern High School as WR Coach/Freshmen HC/OC. As he came into the 2020 season he joined the staff at Franklin County HS in Frankfort, KY as B-Back Coach, after going through a covid-19 full fall season, that resulted in playing in the state championship game in class 4A. He then relocated to Kennewick, WA and was able to join the staff at Kennewick High School for a spring football season. Coach Dunnigan currently resides in Kennewick, WA