The victim, a 63-year-old, was stabbed in the chest and arm and died at one of Turin's hospitals.
The man and his assailant began arguing in a bar late yesterday over Inter's fielding of too many foreign players to be truly considered an "Italian" team, according to ANSA's reconstruction of events.
Police would not immediately comment on the matter.
Inter beat Bayern Munich 2-0 at the Santiago Bernabeu stadium in Madrid yesterday to become the first Italian team to achieve the treble of Serie A, Italian Cup and Champions League.
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