Haaland appeared to signal to Norway coach Stale Solbakken that he wanted to come off shortly before the hour mark, with the score level at 1-1.
The 26-year-old eventually left the pitch in the 67th minute and appeared to be limping as he made his way off, raising concerns about his condition just days before City face Liverpool in a major Premier League clash.
It remains unclear whether Haaland was carrying an injury or simply suffering from fatigue or cramp. He has played more than five-and-a-half hours of international football across three countries in less than two weeks.
Solbakken was quick to play down the concern, insisting that Haaland had always been scheduled to be replaced during the second half.
However, the sight of one of the world's most physically imposing forwards leaving the pitch uncomfortably will still concern City, particularly with a demanding Premier League fixture against Liverpool approaching.
City will want Haaland assessed as soon as he returns to the club before deciding whether he is fit to feature at Anfield.
The striker has been central to City's strong start to the Premier League season, and his availability could be crucial as Enzo Maresca's side look to maintain their perfect record.
For now, City will be hoping Haaland's early departure from Norway duty was simply precautionary rather than the start of another injury problem.
