By ESPNSTAR.com staff
Buttner, 23, was acquired over the summer from Dutch side Vitesse and impressed on his debut against Wigan as he skipped past several defenders and scored a virtuoso goal.
Since that game, the youngster has made three more appearances in a United shirt and many have declared him to be Evra's likely long-term successor.
Evra has struggled of late to demonstrate the form that earned him the captaincy last season but he remains the undisputed first-team starter under manager Sir Alex Ferguson. And Silvestre leapt to the defence of his compatriot as he believes that the player's extended participation in competitive football for both club and country has taken its toll on him.
Silvestre also stated that he has also been impressed by Buttner's showing in the Wigan game and backs him to continue shining for United over the season.
"I only saw the highlights of the game when Alex started and scored [against Wigan Athletic]. It doesn't get better than starting at Old Trafford and scoring a goal," he told manutd.com.
"Patrice has been there and has been solid in this role, but there hasn't been any cover for him so he has played a lot of games for United and France.
"That has demanded a lot of Patrice and it is important to keep the players on their toes and to have fresh legs.
"There are so many games so you need to rotate at some point. Especially because United full backs do not just sit back and defend, they go and attack and provide width too."
Silvestre was recently released from his contract by Werder Bremen and has been given permission by Ferguson to train at Old Trafford. He insists that he is still keen to play top-flight football at the age of 34 and remains optimistic of signing a deal with a new club soon.
"I am back here to train. I came a few weeks ago and had a chat with the gaffer just before the Capital One Cup game. I said I was coming back to Manchester until Christmas and he said, 'Come and train and stay fit until you move to somewhere else'.
“When you are training with the lads you feel like you are still capable of playing in the Premier League. I am fit, that is the main point, and I still have the hunger for the game.
"So this level [the Premier League] is still the level that I am targeting.
"I keep thinking about what I will do when I stop playing but I am not sure. Football is my life of course, but I don't know in which position or area I might stay on."
Silvestre made 361 appearances over a nine-year period and left, somewhat controversially, to join Arsenal in 2008.