Zlatan Ibrahimovic says he played through the pain of a serious knee injury to help AC Milan win their first Serie A title for 11 years.
The Swedish forward, 40, had surgery on Wednesday and is expected to be out for up to eight months.
"I have never suffered so much on and off the pitch. Barely slept for six months because of the pain," Ibrahimovic wrote on Instagram.
Milan have called the procedure on his left knee "a complete success".
Ibrahimovic, who is out of contract in the summer, has expressed a desire to stay with the club for at least one more season.
And while he endured a stop-start campaign because of injuries, he contributed eight league goals as Milan edged out another of his former clubs, and city rivals, Inter to win the Scudetto.
"I was only able to train with the team 10 times in the last six months," wrote Ibrahimovic.
"For the last six months I played without an ACL [anterior cruciate ligament] in my left knee. Took more than 20 injections in six months. Emptied the knee once a week for six months. Painkillers every day for six months.
"I made something impossible to something possible. In my mind I had only one objective, to make my team-mates and coach champions of Italy because I made them a promise. Today I have a new ACL and another trophy."
The former Manchester United and Paris St-Germain frontman returned to the San Siro in 2020 having also won a league title during his first spell at Milan.
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