Matt Ellerbrock is in his second season as the Illinois football program's assistant linebackers coach in 2026. Ellerbrock joined the Fighting Illini in 2025 with a decade of college coaching experience.

In his first season in Champaign, Ellerbrock helped the Illini to nine wins, a victory over #23 Tennessee in the Liberty Mutual Music City Bowl, and a final ranking of #25 in the Coaches Poll. Ellerbrock helped the defense have its best game of the 2025 season in the Illini's Music City Bowl victory over Tennessee, holding the Volunteers' offense, which ranked fourth in the nation in yards per game, to a season-low 278 total yards. Illinois held Tennessee quarterback Joey Aguilar to a career-low 121 passing yards, 53 fewer than any other game in his career, and snapped his streak of 36 straight games throwing for more than 200 yards. 

In his career, Ellerbrock has coached in six bowl games including helping Illinois win the 2025 Music City Bowl and Houston to a victory in the 2022 Independence Bowl over Louisiana. He spent four seasons over two stints at Houston, including working as a defensive analyst under current Illinois linebackers coach Archie McDaniel from 2022-23. 

The 2022 Houston team reached as high as No. 24 in the AP poll in its final year in the American, before Ellerbrock helped the program in its transition to power-conference football in the Big XII in 2023. In 2024, Ellerbrock transitioned to IMG Academy, where he coached the team's linebackers. 

Ellerbrock also worked at Houston from 2019-20 as a defensive graduate assistant focusing on linebackers and safeties, before spending the 2021 season as the linebackers coach at McNeese State. He coached McNeese's All-Southland Conference First Team honoree Kordell Williams, who registered 100 tackles and ranked fourth in the Southland with 9.1 tackles per game. 

Prior to his first stint at Houston, Ellerbrock spent two seasons at Arkansas State from 2016-18 as the program's defensive graduate assistant working with linebackers and safeties. Arkansas State was one of the best in the country at defending the pass in 2017, ranking 11th in the nation in passing defense at 177.8 yards allowed per game. In his first season at Arkansas State, Ellerbrock helped the Red Wolves to an 8-5 overall record, a Sun Belt Conference championship with a 7-1 league record, and a 31-13 victory over UCF in the 2016 Cure Bowl.

A four-year starter at Midwestern State, Ellerbrock got his start in coaching as a graduate assistant at his alma mater in 2013, then moved on to Stephen F. Austin as a graduate assistant from 2014-15. 

As a player at Midwestern State, Ellerbrock was a two-time Honorable Mention All-Lone Star Conference performer and helped lead the program to three Lone Star Conference championships and postseason play every year. He started 44 of 46 career games and totaled 231 career tackles, 28.0 tackles for loss, and 7.0 sacks. Named a captain as a senior, Ellerbrock was honored as the Lone Star Conference Defensive Player of the Week for his performance in the LSC championship-clinching win at No. 12 West Texas A&M.

Ellerbrock earned his bachelor's degree in sport and fitness management from Midwestern State University in 2012. He earned his master's degree at Stephen F. Austin State University in secondary education in May 2016.

Ellerbrock and his wife, Samantha, have one daughter, Ariella.