Guardiola wary of 'aggressive' Leeds in City's Premier League restart
City, who lost to Brentford in their final league game before the World Cup break, trail leaders Arsenal by eight points. Newcastle United have leapfrogged Guardiola's side into second, a point above City but having played two games more.
Guardiola said his players had to be switched on against Leeds.
"One of the toughest games, I would have preferred another opponent than Leeds in the moment after the World Cup. It's the most aggressive team in the Premier League," he added.
"Their guys don't give you time to think. You have to be precise and you have to be in a high level to do it in the situation we have after our defeat against Brentford."
City can cut the deficit to Arsenal to five points with a win on Wednesday and Guardiola was determined to keep the leaders within striking distance.
"You have to be alert and be careful because if the distance is bigger, it'll be so difficult to catch them."