Newcastle United yesterday confirmed that Barton will be staying on the St James' Park payroll with his existing £65,000-a-week salary intact.
Leo Sandino-Taylor (Nike spokesman): "While Joey Barton is a talented footballer, we cannot condone or accept what he did and his contract has been terminated.
"We have provisions in all our sponsorship contracts to take into account any actions by athletes that bring the brand into disrepute."
It is understood his two-year arrangement with the company is believed to have been worth £40,000 a year.