The English side maintained their 100 per cent start to their Champions League campaign with an emphatic win at the Orange Velodrome.
The visitors drew first blood 18 minutes into the game when summer-signing Ferran Torres gave City the lead from close range.
Marseille kept Guardiola’s men at bay for vast majority of the game until Germany international IIkay Gudogan found Manchester City’s second on the 76th minute mark, and Raheem Sterling tapped home from Kevin De Bruyne trademark delivery five minutes later to take the game beyond the Frenchmen.
Speaking to the media after the game, the Spanish coach hailed his team’s performance in France.
"We played really well, we didn't concede and we were in control, patient and aggressive without the ball. I'm so satisfied with the performance and result, it's always difficult to win away,” Guardiola said.
"We can play on both sides, we tried to play high and wide to stretch the pitch. Raheem Sterling was exceptional, Phil [Foden] as well. We didn't expect them to play five at the back until we saw the team. Porto was the same. As much as we play against five at the back we started to take the control and rhythm.
"We were so stable defensively. Aymeric [Laporte] was good, Kyle [Walker] is in the best form since we've been together, Oleksandr [Zinchenko] helped us, John [Stones] played good minutes. I'm so satisfied with the way we played."