Milan won the match—securing a 3-1 victory with goals from Andrea Bertolacci, Philippe Mexes and Carlos Bacca—but their triumph came at a cost.
Centre-back Alex was knocked unconscious after being hit in the head during a collision with young goalkeeper Gianluigi Donnarumma on 50 minutes.
The former Chelsea defender was struck by the 16-year-old’s knee and dropped to the turf, unresponsive. The stricken player was subsequently replaced by French stopper Mexes, who bagged Milan’s second.
Alex later regained consciousness in the dressing room, and was subsequently taken to a hospital in Rome, where he will spend the night.
The experienced 33-year-old campaigner’s absence will represent a loss for Sinisa Mihajlovic’s side, who have finally found some consistency over recent weeks.
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After struggling defensively, the Serbian coach opted to introduce teenage stopper Donnarumma, whose arrival coincided with an upturn in fortunes.
The loss of Alex, an experienced counterpoint for the youngster, could well set the Rossoneri back.