Zlatan Ibrahimovic revealed he has "never suffered so much" as he did in the past six months after the Milan striker underwent knee surgery.

The new Serie A champions on Wednesday revealed Ibrahimovic will be out for up to eight months following an operation on his left knee.

Ibrahimovic came off the bench in a 3-0 win over Sassuolo on Sunday that sealed the Rossoneri's first Scudetto for 11 years.

The 40-year-old Sweden striker only started 12 games for Stefano Pioli's side this season and with his contract expiring at the end of next month, his future is up in the air.

Ibrahimovic on Thursday opened up on the pain he has experienced this year.

"For the past six months I played without an ACL in my left knee," he posted on Instagram.

"Swollen knee for six months. I was only able to train with the team 10 times in the last six months.

"Took more than 20 injections in six months. Emptied the knee once a week for six months. Painkillers every day for six months.

"Barely slept for six months because of the pain. Never suffered so much on and off the pitch. I made something impossible something possible.

"In my mind I had only one objective, to make my teammates and coach champions of Italy because I made them a promise. Today I have a new ACL and another trophy."