The France international defender was dropped by Roma, where he is on loan for the season, that stops Newcastle triggering a contract clause.
He has been in superb form in Italy, so what was so wrong at Newcastle?
Yanga-Mbiwa has played in the previous 19 Roma games, and if he had racked up a 20th this month it would have meant a cash injection for the Magpies.
Roma are likely to make the deal permanent in the summer, or possibly this month if they can haggle on the price.
Yanga-Mbiwa has been recalled to the France squad.