McCarthy prepared himself for bigger tasks as an assistant coach at Belgian side Sint-Truidense VV, just two years after retiring as a player.
Cape Town City offered him his first role as a head coach, and he won the MTN8 in the two seasons he spent with the Citizens.
But more was to come at AmaZulu, whom he guided to finishing the 2020/21 season as Premier Soccer League runners-up, earning himself a chance to coach in the CAF Champions League the following term.
But the epitome of his coaching career is arguably being a forwards coach at Premier League giants Manchester United, before the Kenya role.