Phillips made his City debut as a late substitute in last week's victory over West Ham but will not be part of the squad in our first home game of the new Premier League season.
Our manager also highlighted that Cole Palmer may not feature against Bournemouth due to a foot injury sustained this week.
Speaking in his usual media briefing on Friday, Guardiola said: "Kalvin has some niggles and won't be able [to play]. Cole Palmer had a knock in his feet in the last days and is a doubt for tomorrow."
Newly promoted Bournemouth began the season with a 2-0 victory over Aston Villa last week and Pep expects the Cherries to be a difficult proposition this weekend.
"When they are promoted, the first few games they are so dangerous," he said.
"They don't feel the pressure, they still feel good from the previous season, they have nothing to lose.
"After one, two, three months all the teams have problems with injuries. Bad moments, mood in locker room - these things always happen. But in the first few games every team is there pushing to do better."
City v Bournemouth
Our Matchday Live show begins one hour before kick-off and is available on all our digital platforms, including our Matchday Centre.
And, during the game, you can listen to live audio commentary in the Man City app.
Short highlights will be available to watch on Saturday evening, while CITY+ subscribers will also be able to enjoy every minute of the action in our full-match replay from midnight.