Granero, 26, left Real in August 2012 to join QPR before the Spaniard was loaned out to Sociedad with his English side in the Championship.
The Madrid-born Granero hopes to see his former side win La Liga, which is topped by their rivals Atletico Madrid ahead of Barcelona and Real.
Granero has been sidelined since September last year with a knee injury, and is pleased to be returning against Real.
"I would like to see Madrid as champions but losing to us would complicate things for them," Granero said.
"It's special to come back from injuries against this opponent and it will be more emotional.
"I feel good. I'm ready to play and it's up to the coach. He makes the decisions."
Granero is desperate to get back playing as Sociedad look to qualify for the UEFA Europa League, sitting sixth and a point ahead of Villarreal.
"We've done all kinds of tests, I feel fine and my rhythm is good, but now I need to play and the sooner I can do that, the better," he said.
