City appeared to be cruising to only their third win in 13 attempts after first half goals from Lewin Nyatanga and Nicky Maynard but a terrible mistake from goalkeeper Dean Gerken let the Championship leaders back in and Andy Carroll ensured that they left Bristol with a point.
Related ArticlesBarton thanks Newcastle fans for supportNewcastle 'no longer for sale'Championship tableTelegraph player raterChampionship fixturesSport on televisionWith their new man in charge, City started brightly and went ahead ten minutes in using a free-kick which looked as if it had been messed up in its execution.
But the Newcastle United wall didn't react quickly enough and Nicky Maynard's low shot was fumbled by Steve Harper allowing Lewin Nyatanga to poke in the rebound for his first ever City goal.
Rumours had spread during the week that Johnson, who left after four and a half largely successful years at the helm, had lost the confidence of City's players, with one allegedly being involved in a dressing room incident with the outgoing manager at Tuesday's defeat at Plymouth, but those same players were certainly working hard for the caretaker boss.
A superb individual effort from Maynard doubled the advantage before the break. He collected the ball on the left, cut inside and unleashed an unstoppable shot from 25 yards which went in off the post.
City sat back in the second half and Gerken made a couple of excellent saves before gifting the visitors a lifeline.
His short throw aimed for Cole Skuse instead went straight to Jonas Gutierrez who was then almost able to walk the ball into the net.
Three minutes later, Wayne Routledge broke down the left and his ball found Carroll in acres of space to equalise. Gerken at least made amends by denying Leon Best late on as Millen and his team desperately hung on for their point.