Giggs, 37, created both goals for United in last night's Champions League win over Chelsea.
"Giggsy is incredible," Rooney told the talkSPORT. "What he does for Manchester United and what he does for the younger players at the club is amazing.
"It's absolutely fantastic to play with him and for me he's a genius. I don't think it will be long before we're calling him Sir Ryan, to be honest.
"The same goes for Scholes. I've always said I think he's the best footballer I've ever played with. His vision, passing, everything about him is world-class, and for him and Giggsy to still be doing what they're doing and giving the performances they are at their age."