Standing in the centre of the ring at the Saudi Airlines Club, the Ukrainian unified heavyweight champion lined the coins up on his hand, wrist and arm before flicking them into the air and catching each one.
It was an impressive display of dexterity and was the centrepiece of a 10-minute session that also included some dance moves.
He wore a T-shirt showing the colours of the Ukrainian flag with the slogan 'Colours of Freedom', a reference to his nation's war with Russia.
At Monday's arrival event, he carried under his arm a stuffed toy donkey that was given to him by his daughter before he joined the war effort, from which he was eventually given dispensation to defend his WBA, IBF and WBO belts in Jeddah.
Joshua hit the pads with new trainer Robert Garcia while assistant coach Angel Fernandez watched from the corner and, when questioned at the end of the session, the fallen champion predicted he would knock Usyk out in their rematch.
"Previous experience against him is helpful but it's all about the night, so I don't know how much it will help," Joshua said.
"From all my experiences I have learned liked a sponge, but ultimately Saturday night is a fight and that's what it's all about, that's it. I'll just do my best, that's all I can do."