The midfielder scored his side's opener in their 2-1 Copa del Rey second-leg win over Athletic Bilbao and praised his side for their reaction in the second half
Garcia scored his side's equaliser in the quarter-final second-leg with Athletic Bilbao before Diego Costa sealed a 3-1 aggregate win with a late strike on Wednesday.
Atleti will now face their bitter city rivals in a repeat of last season's final, and Garcia has stressed his side are fired up to retain their trophy.
"At half-time we talked about being a team of men and stand up, as we have always done when things are bad. We did that," he was quoted as saying by AS after the match.
"The first 30 minutes from the team was good and we had our chances, but the game changed with their goal. Am I happy with mine? It was business as usual - the important thing is that the team needed it.
"We know games against Madrid are special, but we want to play a good tie and reach the final. We've had a difficult January but we've responded. We're not worried. We want to be in the final, of course."
Atletico had Thibaut Courtois to thank for pulling off a series of impressive saves to prevent his side from going 2-0 behind on the night, and Garcia hinted he would be thrilled to see the on-loan Chelsea man extend his stay at Diego Simeone's side.
"He's staying until the end of the season. We know he is one of the best keepers in the world right now, but when the season finishes, we'll see," he added.