Giampaolo Pazzini’s brace was ultimately enough to give Milan three points, though a Philippe Mexes own goal gave Bologna late hope.
Elsewhere, Catania stunned Genoa, Siena beat Sampdoria in an ill-tempered match and Parma stalled in Verona.
Torino thumped Pescara at the Adriatico, while Atalanta-Cagliari started 30 minutes late.
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