Inter were beaten 1-0 to put their last 16 hopes in doubt.
Bastoni said afterwards: "There is great disappointment because we made a great effort from a physical and mental point of view, they are among the strongest teams with the ball. It's a shame about the last episode because we didn't deserve it.
"We have played many games against strong teams, they are one step ahead of everyone with the ball. We played a great game in terms of sacrifice and it's a shame about the goal we conceded in the final minutes."
Inter are next in action against Lazio and Bastoni added: "After a defeat there is always a great desire for revenge, we must put this game behind us immediately because another very difficult challenge awaits us."
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