The Premier League champions travel to the East Midlands for an early kick-off on Saturday, not long after the Norwegian forward was substituted in the midweek draw at Borussia Dortmund.
“He feels better but we're training in a few hours and we will assess,” Guardiola told reporters on Friday.
“We will see how he feels. After we will decide - I will know it in two hours if he can play.”
Guardiola is confident that Julian Alvarez can step up and replace Haaland if he cannot make the starting XI to face Leicester as City look to leapfrog Arsenal atop the table.
“Normally if Haaland doesn't play, then Alvarez is the first option to replace him," Guardiola said.
“If Erling is not available, not only tomorrow but in the future, then Julian is the first option.
“Play 90 minutes every game and he will score goals. Maybe not like Erling, but I don't judge him [on goals alone].”