Mick Gatto's son-in-law must serve at least a decade in prison for attempting to possess 22 kilograms of cocaine imported from Mexico that was hidden inside Xerox printers.

Danny Awad – who is married to the underworld figure's daughter Sarah – was on Tuesday jailed for 15 years and must spend 10 years in prison before he is eligible for parole. His jail term came days after high-profile supporters, including his father-in-law, filed character references for him.

Sarah Gatto leaves court on Tuesday after her husband was jailed for 15 years. Credit:Justin McManus

Awad's partner in crime, John Tambakakis, was also jailed for 15 years with a non-parole period of 10, in a County Court room packed with family members and supporters.

Both men showed no reaction as Judge Mark Dean handed down the sentences, but as they were led into custody Awad said "relax" to a group of women sitting in front of the dock – including Ms Gatto – who were sobbing.