Erling Haaland, Antoine Semenyo, Rodri, Rayan Cherki and Tijjani Reijnders all started for the Premier League side, who were 4-0 up at half-time.
Caldwell says he will take the insight he got from Guardiola and the game into Exeter’s second half of the season as they look to continue to pull away from the League One relegation places.
“You’re coming up against one of the best teams in the world, let’s make no bones about it,” he told BBC Radio Devon.
“The team that they put out has got a Ballon d’Or winner in it, it’s got the best number nine in the world, who when he finishes playing probably one of the best number nines of all time in terms of goals that he’ll score at the end of his career.
“It’s got probably one of best managers of all time, and the best at the moment, so we knew the level was big, we knew the challenge was big and we got the full force of their three draws that they got before.
“To get that sort of insight is an amazing experience for me, for the staff and all he spoke about was running, all he spoke about was competing.
“He didn’t speak about how he coaches the team, how he rotates players, the style of football he plays, he coached about running and getting people to fight and it was great to hear because we’ve been speaking about it for years at this club.
“To hear it from one of the very best was really good to hear and we have to pick up those little nuggets, learn those little lessons and take it forward and try and help Exeter be better now and and in the remaining games this season.”
