A tapped phone call between Mick Gatto’s son-in-law and an associate led police to investigate a Melbourne soccer game in a match-fixing probe that ended up costing the team's coach his job.

Danny Awad was under investigation for attempting to possess 22 kilograms of cocaine imported from Mexico when on August 19, 2017 police overheard a call he took from property developer John Khoury, a business partner of Mr Gatto's.

John Khoury, left, with Mick Gatto. Credit:Erin Jonasson

Khoury asked Awad, who is married to Mr Gatto’s daughter Sarah, to place a multi-bet on his behalf, having learnt from a source that soccer club Dandenong Thunder was to field a weaker side in its game that day.

Khoury bet $4000 and stood to win $43,300 if Thunder lost its game and his pick for a Queensland horse race came in first.