The 21-year-old suffered a freak injury on Saturday during Villa’s final pre-season game against Watford. A collision with Tom Cleverley left Grealish on the ground in pain holding his ribs and it later emerged that the impact had caused a bleed in one of his kidneys.
Grealish’s father confirmed the extent of the injury on social media, posting a message on the player’s behalf.
“Absolutely devastated.. got a nasty elbow to the stomach in yesterday’s game which caused a bleed in my kidney,” he said on Facebook.
“Had a mini op early this morning and will now be out for at least 2-3 months.
“Gutted as season was about to start next week but will be doing everything to come back fitter and stronger. Upthevilla.”
News of Grealish’s injury comes just days before Villa begin their Championship campaign against Hull at Villa Park on Saturday.
The Villa academy product scored five goals in 33 appearances for the club last season.