Manchester United captain Harry Maguire (AFP)
Ralf Rangnick's men needed a 71st-minute equaliser from half-time substitute Edinson Cavani after Allan Saint-Maximin scored a superb early opener, and were indebted to David de Gea for a series of fine saves.
It was United's first match since December 11 after a Covid-19 outbreak forced them to close their training complex -- Victor Lindelof was absent from St James' Park after testing positive.
"No 16-day break in the middle of a football season is going to help you," Maguire told Manchester United's official website.
"The training ground has been shut and half the lads playing today are recovering from the virus, so of course it's not going to help us.
"We've had people with symptoms, people without symptoms -- it's been a real mixed bag for everyone at the football club and it's been a tough time."
But the England international defender said United could not make excuses for their sloppy performance.
"We've got to stay on the ball, we've got to stay active and we've got to play the ball in their half and we didn't manage to do that," he said.
"You can look at that and ask whether the last 16 days had a big impact on that because it looked like we ran out of steam out there.
"A point in the end is a fair result, but it's a result that we're disappointed with."
The draw means United are seven points behind fourth-placed Arsenal with two games in hand ahead of Thursday's clash with Burnley at Old Trafford, but Maguire said they would be better after their tough evening at Newcastle.
"I'm sure 90 minutes will have benefitted every single player out there," he said.
"The Burnley game and the Wolves game are coming up thick and fast and we've got to play better than we have done tonight to make sure we get three points."
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