Newcastle midfielder was able to mantain his $141,000 per week salary when Coach Kevin Keegan welcomed him back to the club after his prison stint for violent assault, but Nike has terminated Barton's sponsorship deal.
Leo Sandino-Taylor, a Nike spokesman, said: "While Joey Barton is a talented [soccer player], 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."
Barton's two-year arrangement with Nike is believed to
have been worth $80,000 a year.