Zac Williams is in his fourth season on the Illinois staff in 2026. Williams, who was hired in July 2023, is an assistant athletic trainer working with the Illinois football team.

During his first three seasons Champaign, Williams has helped the Illini to 24 victories, two bowl wins, and back-to-back seasons with 9+ wins for the first time in program history. Over the last two seasons, Illinois has won 19 games, the program's most ever in a two-year span, including 15 Power-4 wins (the fourth-most in the Big Ten), six ranked wins, and two bowl victories over SEC opponents in the 2024 Citrus Bowl vs. #14 South Carolina and 2025 Music City Bowl vs. #23 Tennessee. 

Williams came to Champaign from Lexington, Kentucky, where he spent two years completing a fellowship with the Wildcats football team. Prior to Kentucky, Williams worked as a graduate assistant for Penn State Wilkes Barre.

As an athletic training student, Williams worked with the men's basketball, baseball, and track & field teams. Williams also served as a student intern for the Cincinnati Bengals during the 2017-2018 season.

Williams completed his undergraduate degree in athletic training from Cedarville University where he also minored in bible and psychology. He received his master’s degree in athletic training from East Stroudsburg University.

Williams is originally from Pennsylvania and now resides in Champaign, Illinois.