The summer signing from Borussia Dortmund sat out of the 2-1 win in Houston, Texas as Kevin De Bruyne scored twice for the Premier League champions.
Other new arrivals Julian Alvarez, Kalvin Phillips and Stefan Ortega all featured, so fans may have been worried as to why Haaland did not get on the field in the States.
Guardiola revealed that he was not quite ready to make an appearance for his new team, but he will be when City take on Bayern Munich in their next friendly at the weekend.
‘Next game he will be ready,’ said Guardiola. ‘He had niggles and a few problems. We’ll see. He’s trained just two sessions and we didn’t want to take risks. The season is so long.
‘He had problems last season and tried to handle it. We want to take care of him and want him fit.’
Haaland does not have a huge amount of time to get settled into his new surroundings before the Premier League season starts, with just one more friendly against Bayern, the Community Shield against Liverpool and then the season opener against West Ham on 7 August.
Guardiola was impressed by Alvarez, who started the game, comparing him to now former City player Gabriel Jesus for his defensive work.
Haaland is expected to be first choice up front this season, but he will have competition from the Argentinian.
‘Julian was incredible, defensively he is quite similar like Gabriel,’ said Guardiola. ‘Gabriel is probably the best, but he is close to him in aggression and how intuitive he is, he makes the runs and with the ball he’s absolutely brilliant.
‘He can keep the ball and you can link with him without a problem.
‘We have the feeling we signed a top-class young player for the next years to come, and we are delighted.
‘The job that Mareclo Gallardo did at River Plate, we have the benefit, and hopefully he can grow up in an important league like Premier League.
‘All the young lads did really well, and Stefan (Ortega Moreno), he did well. We are impressed with how good a keeper we have now – his composure, we are impressed.
‘Kalvin, he already knows perfectly (the Premier League) – he needs time to understand what we want him to do and help him with his movements and shapes. We are very pleased.’
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