The defender was replaced at the break during last night’s 2-1 defeat to Arsenal at St James’s Park.
Good missed the first half of the season through injury, having suffered a hip problem playing for Australia last March.
And the 21-year-old – handed the captain’s armband – was taken off as a “precaution”, according to football development manager Peter Beardsley.
“I think he’s OK, but at this level I almost encourage them to come off (if they have a problem),” Beardsley told the Gazette.
“If they’re struggling, I always say ‘come off’. He wasn’t sure.
“I wasn’t anything major, I don’t think. It was a precaution – we just needed to make sure he was all right.”
Newcastle were beaten by a 90th-minute goal from Arsenal’s Austin Lipman.
United’s Dan Barlaser had cancelled out Alex Iwobi’s first-half strike with a well-executed volley in the 56th minute after Arsenal failed to properly clear a ball from Adam Armstrong.