Steve Bruce cut a frustrated figure in the Manchester rain after his side's 5-0 defeat at the hands of last season's Premier League champions.
Man City ran out easy winners as Newcastle barely laid a glove on the home side to end United's six-game unbeaten run.
The defeat also knocked the Magpies down to 13th in the table and they will be thankful relegation has now been fended off.
Bruce said: "An interview in the rain after being beaten 5-0, painful?
"Not as half as painful as watching that.
"We are disappointing but they were far too good for us, we have to do better, we gifted them some goals and you cannot do that against a team of this calibre."
Newcastle played the game without Jamaal Lascelles, Miguel Almiron and star man Allan Saint-Maximin.
Bruce added:"We cannot be without six and seven of our better players, certainly at a place like this, this was one too far. T
"hey proved today on their day they are too good for us."
Now United must bounce back against Watford on Saturday.
Bruce said: "We have had one or two moments this year and have bounced back but we have to be mentally ready and mentally better than what we have done tonight.
"I will make sure on Saturday [against Watford] we will be ready."
