A cannabis suspect burst into tears when confronted by police officers in East Kibride.
Police then recovered £25,000 worth of the drug from Darius Jack's car and Ayrshire home.
Jack, 21, of Newmilns, was jailed for 15 months at Hamilton Sheriff Court this week.
He admitted being concerned in the supply of cannabis in Main Street, East Kilbride, at his home and elsewhere on April 8 last year.
Chloe O'Hara, prosecuting, said police officers spoke to Jack in a car park in East Kilbride after following his vehicle.
She stated: "There was a strong smell of cannabis coming from his car.
"The accused appeared to be nervous and when the officers spoke to him he became tearful and said 'I'm sorry. I'm caught'.
"He was then detained for a search under the Misuse of Drugs Act."
Bags of cannabis were found in the vehicle and in the living room and kitchen of his home.
Ms O'Hara said that, in total, cannabis weighing 4.2kg was recovered. Some of it had been divided into the most common 8g deals.
Jack, who has no previous convictions, claimed his involvement was limited to holding the drugs for another person.
His solicitor told the court: "He, perhaps, has exhibited some immaturity.
"Since this incident he has endeavoured to distance himself from anyone involved in this type of behaviour.
"He accepts he is the one who made a bad decision here."
The solicitor suggested a community-based sentence could be imposed, but Sheriff Thomas Millar told Jack:
"This is a serious matter involving more than 4kg of cannabis.
"It's not a minor matter and I'm afraid custody is the only option.
"It would have been 20 months, but I'll reduce that to 15 months in light of your guilty plea."
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