Vidic's move to Italy was confirmed in March after the star rejected the chance to renew his United deal, with the Serbian's medal haul from his time at United including five Premier League titles and the Champions League in 2008.
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|7/1||Nemanja Vidic is 7/1 with Bet365 to score anytime against Hull in United's next fixture|
The Frenchman is also out of contract in the summer and is weighing up his options before deciding whether to contiune with the club next season.
"It's painful to lose Vida," the Frenchman told the United official website. "For me, he is a great centre-back. When you see a player like Vidic leaving the club, you feel really sad.
"When you speak about Vida, it's like you're speaking about myself. We joined the club together. I remember the first game was so hard. In one match, we played in the reserves together. We were so poor.
"Rene Meulensteen was the [reserve team] manager and he took us both off. We were talking in the dressing room and saying: 'Oh my, why have we come to Manchester? We should go back to our old clubs'.
"It was a difficult moment but we stuck together. We've been in the same hotel going into training and, together, we've won the same trophies. I'm really sad to lose him."