Köln confirmed the appointment on their official website on Wednesday. McKenna will link up with head coach Rene Wagner's staff ahead of the new season.
Thomas Kessler, the club's sporting managing director, provided the official assessment of the appointment.
"Kevin brings a wealth of experience through his positions as assistant coach at various traditional clubs and in the Bundesliga. At the same time, he knows FC Köln very well from his own past.
"His experience, his professional expertise and his personality will be an enrichment for our coaching team. We are delighted to welcome him back to the FC family."
McKenna first worked as assistant at Köln from 2021 to 2024, a period that encompassed one of the more turbulent chapters in the club's recent history — Bundesliga football, European competition, and relegation all arrived in quick succession. Following his departure from the Rheinenergie Stadion, he joined Steffen Baumgart's coaching staff, working as co-trainer at Hamburger SV and subsequently Union Berlin.
As a player, the Canadian-born McKenna spent the majority of his senior career in Germany, playing for Köln across two separate stints — and going on to captain the club. He made over 200 appearances for the Geißböcke across those years. His connection to the club runs deep enough to describe the return as more than professional.
Wagner, who took charge in the summer of 2025, will go into his second season with the full coaching structure now in place.
The reunion means Cologne's coaching setup now combines the head coach's developing tactical principles with a co-trainer who has lived the club's culture at every level.