The defensive pair played alongside each other for eight-and-a-half years at the Red Devils, where they won five Premier League titles together.
Evra, who left United in 2014, has since been a regular for Serie A champions Juventus, where he has enjoyed further success, winning two league titles and two Coppa Italias.
The full-back also started France's Euro 2016 opener over Romania on Friday, as the hosts began their campaign with a 2-1 win.
Evra gave away a penalty in that game and endured a largely difficult evening in Paris, but he is still likely to be a key part of boss Didier Deschamps's plans.
And Ferdinand has joked that he is surprised to see Evra in the team, claiming the Frenchman looked to be on his way out during his final season at Old Trafford.
France's Patrice Evra celebrates at the end of the match
Speaking on his vlog, Ferdinand said: "Patrice Evra is still playing you know. It's unbelievable.
"When he was at Manchester United I thought, 'wow, this guy's legs are not looking good.'
"He's played for three more years!"
Despite Ferdinand's light-hearted jibe, the pair remain good friends, with Evra's response to his former colleague suggesting they are still in regular contact.