Musannaf Ibn Abi Shayba 13:343

'Abd al-Samad ibn 'Abd al-Warith narrated to us, from Jarir ibn Hazim, who said: Hammad was asked about a man in whose hand is a pledge, and he said: "It is worth ten," while its owner said: "It is worth one dirham." He said: "The burden of proof is upon the one who claims the excess, just as if he said: 'It is a pledge,' and its owner said: 'It is a trust (wadi'ah),' then the statement is the statement of the owner of the goods."