Manchester City forward Erling Haaland has been dealing with muscle discomfort, according to manager Pep Guardiola.

The Norwegian striker was substituted at half-time for the second consecutive match during their preseason tour in the United States.

City lost 4-1 on penalties to Barcelona after a 2-2 draw in Florida.

Haaland was also taken off at half-time during their 3-2 defeat to AC Milan in New York over the weekend.

"He's got some niggles. He didn't feel good," Guardiola said on Tuesday. "[It is] disturbing something, he doesn't feel comfortable.

"Muscular niggles is not worth the risk. Sooner or later he has to take a step. To lose him for three weeks, that would be a problem as 60-70% of the squad are on holiday."

Premier League champions Manchester City will face FA Cup winners Manchester United in the Community Shield on August 10. They will then start their league title defense with a match against Chelsea at Stamford Bridge on August 18.