​Like a lot of Terre Haute youngsters growing up in the early 2000s, Chris O’Leary spent plenty of hot summer days trying to get Peyton Manning’s autograph during the Indianapolis Colts’ preseason training camps at Rose-Hulman.Those took place here for 11 consecutive years (1999-2009).But O’Leary — usually joined by his father Patrick and brothers Marc, Dan and Matt — didn’t just focus on the future Pro Football Hall of Fame quarterback with the large forehead and even larger ability to stage miraculous comebacks. Chris also noticed Dwight Freeney (another future Hall of Famer), Robert Mathis, Bob Sanders and Cato June on the defensive side of the football.”I was a diehard Colts fan when I was in elementary school [at Sugar Grove] and middle school [at Woodrow Wilson],” Chris O’Leary said during a recent phone interview.So when O’Leary went into coaching after playing quarterback for Terre Haute North High School (graduating in 2010) and QB and wide receiver for Indiana State (2011-14 after sitting out 2010 as a redshirt freshman, majoring in physical education), he decided to try the defensive side of the football himself.And he never looked back.First, young O’Leary was a graduate assistant working with the D-line at Georgia State (2015-16). Then he became the safeties coach at Florida Tech (2017), then a defensive analyst/defensive grad assistant at Notre Dame (2018-20) followed by a switch to safeties coach with the Fighting Irish (2021-23).Then O’Leary made a big jump, taking the job as safeties coach for first-year head coach Jim Harbaugh and defensive coordinator Jesse Minter — an ISU assistant coach to Trent Miles when O’Leary played for the Sycamores — with the NFL’s Los Angeles Chargers in 2024.But seeing an opportunity to become a defensive coordinator at an FBS college, Western Michigan, O’Leary bolted there for one season in 2025.Little did O’Leary know, however, Minter would apply for the Baltimore Ravens’ head-coaching position after they parted ways with longtime field boss John Harbaugh (Jim’s brother) following the 2025 season. Minter was hired by the Ravens in January 2026, thus creating an opening for the Chargers’ D-coordinator job.You guessed it. Jim Harbaugh brought O’Leary back to the Chargers to serve an even higher position on his staff.Only 34, Chris O’Leary is already an NFL defensive coordinator.I I IWhile I had O’Leary on the phone during a break in practice, I asked him to describe three major influences on his football career — Minter, Miles and Jim Harbaugh.• On Minter: “Jesse has been a mentor of mine in coaching. I really view him as the one who taught me defensive football, taught me at my first stop [Georgia State, where Minter coordinated the defense for Miles after they left ISU] how to operate as a coach. Ever since then, I had stayed in touch with him two or three times a year. Then, obviously in 2024, I was able to work with him out in L.A. He’s meant everything to me in coaching.”Did Minter pu