The 35-year-old Welshman came on as a second-half substitute against Stoke City at the Britannia Stadium and set up goals for Berbatov and John O'Shea to secure a 2-0 win that moved United to the top of the Premier League.
Berbatov said: "The game changed when Ryan came on. He makes the right decisions. That is what got us the three points. You can see because of the number of years he has been able to play for Manchester Untied how much he helps by being on the pitch."
United manager Sir Alex Ferguson threw Giggs into the action after watching Nani and £16 million summer recruit Antonio Valencia struggle to break down a Stoke side that Potters manager Tony Pulis later admitted were "flat".
Despite being top of the league the failure of United's other widemen to hit form must be a worry for Ferguson, who has repeatedly called on Giggs to spark United into life this season.