On their official Twitter account on Tuesday, Milan posted pictures from training at the Milanello training facility outside Milan.
The pictures show how the 41-year-old runs, shoots and participates in various training sessions.
Milan in a minor crisis
According to calciomercato.com, Ibrahimovic looked sharp and fully recovered from the long injury and rehabilitation layoff following cruciate ligament surgery 260 days ago.
Milan are in a bit of a crisis after three straight defeats in Serie A and have just one win in their last eight games, all competitions included.
The reigning champions have slumped to sixth in the league, but are level at the top behind leaders Napoli and a Champions League place in the autumn is within reach.
Short drop in on Friday?
Coach Stefano Pioli chose last week not to include Ibrahimovic in the spring squad for the Champions League.
Milan starts the round of 16 game next week, against Tottenham.
Ibrahimovic needs to be matched starting carefully.
Italian media do not rule out that he may make a short appearance already on Friday.
EC qualifier March 24
The national team's national team captain Janne Andersson has repeatedly said that an Ibrahimovic in match form is still relevant for the national team.
On March 24, Sweden begins the EC qualifier against Belgium and three days later Azerbaijan awaits.
Both matches are played at the Friends arena.
Andersson takes out the European Championship qualifying squad on March 15.