Garcia's men begin their Serie A campaign against Fiorentina on Saturday, and were drawn alongside Bayern Munich, Manchester City and CSKA Moscow in Thursday's UEFA Champions League draw.
Despite being keen to temper expectations, Garcia is confident that he has the required depth to compete on all fronts.
"I've read lots of things since the start of pre-season: from euphoria, as if we'd already won, to negative things," he said. "Our main aim is to enjoy ourselves when we play and make sure the fans enjoy themselves too.
"We have a bigger roster this year, it's necessary given the games we have to play. We needed two per position and we have that.
"We'll be missing a few players tomorrow but we have able replacements who can come in.
"My players are ready, they can't wait to start and get stuck into the competitive matches.
"Now we're just thinking about beating Fiorentina, then we'll move on to Empoli and the Champions League. We have a marathon to run this year."
Garcia has recruited a host of new players over the close-season, and outlined his plans for Kostas Manolas, Jaun Iturbe and Salih Ucan.
"Manolas? He's our defender for the future," he added. "I don't know if he'll start against Fiorentina but he's available.
"Iturbe is improving a lot. I've been impressed by his attitude and commitment in training.
"Ucan is a talented youngster. The first thing he needs to do is learn the language, he'll be a very important midfielder for us."
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