Marc Colwell enters his 14th year at Illinois Tech in 2023, which includes the last 10 as head men's soccer coach. (MEN: 119-124-23, 14 seasons; nine at Illinois Tech, five at Lakeland) (WOMEN: 95-80-7, nine seasons; five at Lakeland, four at Illinois Tech) Colwell arrived to Illinois Tech as the head women's soccer coach, a post he held for four seasons from 2010-2013.

He led the Scarlet Hawks to a seamless transition into a full NCAA Division III member in 2018, and has since coached one All-NACC Second Team selection, 54 NACC Scholar-Athletes, and one United Soccer Coaches All-Central Region Third Team athlete. The transition's provisional period resulted in 15 All-Association of Division III Independents selections, five USCAA All-Americans, one Association of Division III Independents Offensive Player of the Year, one Association of Division III Independents Goalkeeper of the Year and one Association of Division III Independents Defensive Player of the Year under Colwell's watch. Colwell landed 2017 Association of Division III Independents Men's Soccer Coach of the Year. 

In December 2021, Colwell was promoted to the position of Senior Associate Director of Athletics, after previously serving as the Co-Interim Director of Athletics since July 2020. He assumed the Co-Interim Director of Athletics position after being the athletic department's Associate Director of Athletics for Operations, a position he held since September 2018. Colwell's administrative duties for the Scarlet Hawks began in May 2012, when he was named Assistant Director of Athletics. 

The South Bend, Indiana native was the assistant women's soccer coach at Saint Mary's College (Ind.) in 2009 after he served as assistant men's soccer coach at Bethel College in 2008, where the Pilots advanced to the NAIA National Tournament that season. He was also the assistant director of coaching for the Junior Irish Soccer Club for three seasons.

Prior to that, Colwell was the head coach for both the men's and women's soccer teams at NCAA Division III Lakeland College in Sheboygan, Wisconsin for five seasons (35-49-12 men) (69-33-3 women). At Lakeland, Colwell guided the women's team to two NCAA Division III Tournament appearances, three conference tournament championships and three regular season conference championships.

Before Lakeland, Colwell served as the assistant men’s and women’s soccer coach at Transylvania University in Lexington, Kentucky. During the 2000-01 season, the women advanced to the NAIA Regional Semifinals and were ranked 10th in the nation while the men finished 13-5-2. Colwell began his coaching career as assistant men’s soccer coach at Earlham College in Richmond, Indiana from 1998-2000. Earlham was a Division III National Tournament participant in 1998 and set a school record for wins in a season in 1999 with a 16-3-1 record.

Colwell obtained his bachelor's degree from Indiana University in 1995. He holds his USSF “B”, NSCAA Advanced National, NSCAA Youth National, and his Scottish Football Association “B” License.