O’Leary brings a track record of rising through the ranks, including a six-year stint at Notre Dame in various roles, and a notable month in the NFL in 2024 as the Chargers’ safeties coach, working directly with defensive coordinator Minter and veteran players such as Derwin James.
His hiring follows a rapid ascent in recent seasons, during which O’Leary earned praise within coaching circles for his development of defensive backs and his ability to translate college schemes to the pro game. That experience on the Chargers’ staff under Minter helped him establish credibility as a potential NFL defensive coordinator.
Independently, O’Leary’s success at Western Michigan stands out. In 2023, the Broncos finished 10-4 and captured a Mid-American Conference title, while the defense ranked ninth in total defense in the FBS, second in MAC scoring defense, and second in MAC total net yards allowed (19th nationally in that category). Those numbers underscored his ability to design a competitive, multiple-based defense at the college level.
In Los Angeles, O’Leary joined a unit that had already shown a meteoric rise under Minter, climbing from a historically inefficient defense to a top-five standard. The Chargers finished strong on defense, ranking first in scoring defense (allowing 17.7 points per game) and holding opposing offenses to limited red-zone success. Derwin James earned his fourth Pro Bowl nod and a second-team All-Pro selection during this arc, and veteran safety Tony Jefferson publicly praised the coaching influence O’Leary provided.
The move signals Harbaugh’s ongoing strategy of cultivating a diverse, NFL-ready staff by promoting and pairing assistants with a proven development track record. O’Leary will join a largely new Chargers staff while the team pursues an intensified defensive identity to complement an offense led by a revitalized coordinator approach. The challenge for him will be sustaining the defensive standard Minter established while aligning with the Chargers’ evolving personnel and a new offensive framework under Mike McDaniel.
