Fernandinho has been sidelined with a hamstring problem since he was forced off in the Carabao Cup final, while Sterling has missed the last four games.
Delph was suspended for three matches, following his red card in the FA Cup defeat to Wigan, but missed the midweek Champions League visit of Basel through injury.
Although Guardiola told press the trio are recovering well, he asserted he will have a better idea of their fitness over the weekend.
Asked of his side’s injury situation, he replied: “Some of them are better.
“Fernandinho and Sterling are much better. Fabian Delph is like this, like that (uncertain).
“We have training sessions to decide before (the game). Today, the players are off so I don’t exactly know the situation.”
With Benjamin Mendy also back in training, Guardiola addressed the importance of having a full squad at his disposal as City enter ‘the business end’ of the campaign.
“We need all of the squad for all of the season,” he added.
“Sometimes, we have injuries but we need all of them.”
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