The 42-year-old was part of the Porto side that won the Champions League in 2004, a triumph which helped propel Mourinho into the world spotlight as a high-calibre coach.
Fast-forward 16 years and McCarthy has since retired as a professional footballer, a career which saw him impress for the likes of Ajax, Celta Vigo and Blackburn Rovers, as well as the South African national team, and is now a coach, having last worked with Cape Town City.
Mourinho, meanwhile, is one of the most successful coaches of the modern era, with a multitude of trophies and a CV laden with illustrious clubs, and his current mission is to help elevate Spurs to the next level following last season's run to the Champions League final.
McCarthy says he will not rush into a new job after being let go by Cape Town City in November and intends to spend some time learning from Mourinho at the Tottenham Hotspur Stadium.
"I'm in regular contact with Jose so I'm going to spend some time at Spurs to see how he operates and what I can learn from him," McCarthy told BBC Sport.
McCarthy also held talks with Ajax Cape Town and Scottish Premiership side Hearts following his departure from Cape Town City.
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