Vidic, who spent eight years at Old Trafford before departing in 2014, claims that Smalling is a true defender and loves the fact he prides his game around the ever-important defensive aspect.
"I've always loved Chris. I love him because he's a defender. His mentality is that he likes to defend," Vidic told manutd.com.
"I believe he can still improve but he is physically strong and, as I said, he likes to defend which, for me, is very important.
"You don't see many players nowadays who like to defend, there are not many in the world. That's his big ability."