Juventus coach Alberto Zaccheroni dismissed Diego's strop during last night's 0-0 draw with Ajax.
The result was enough to see Juve progress to the next round of the Europa League.
Diego was visibly irritated when substituted, but Zaccheroni said: "I didn't notice Diego was annoyed, so I might ask him about it. I can understand his emotions, as nobody likes leaving a game, so it won't be a problem."