City were in complete control for long periods of the game at the Stade Velodrome, where Andre Villas-Boas elected to play with a five-man defence.
It was deemed a cautious by the home side, who rarely threatened the City goal, but Guardiola believes it was his players efforts that restricted Marseille’s play.
“You can play five at the back and be offensive,” he said at his post-match press conference.
“We didn’t expect it because we didn’t see it in their games this season. When we saw three central defenders we suggested to the players, if they play in that way, we should change things.
“If they were not offensive it was because we played good in terms of our pressing. The way we played, we found the spaces we had to attack.
“We saw in the second half that they were brilliant in the first 15 minutes and we suffered.
"I give credit to our team. We didn’t let them play.”
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