Garcia shone with two assists as Real won their tie on Monday night 5-0.
He said at the final whistle: "It was an important win for us. We wanted to start the year strongly and carry over the momentum we'd built up last year. It was a game to keep growing and doing the right things as we have been lately.
“The opposition come into it with excitement and motivation sky high and you have to match that. Any team is strong, especially if you're playing on the road. We've seen others spring a surprise and we didn't want that to happen at our expense.
“It's lovely for Lorenzo, Diego Aguado, Asencio and I, who have come through the youth ranks here. It's great to see that if you do the right things and keep a calm head, you will get your chance, even though it's not easy. I'd like to congratulate them on their performances. Getting a starting place, especially Diego at 17 years old, is a big deal.
“I don't have much advice. It's about showing faith and motivation, and when you come through the ranks, you'll have plenty of that. They had to stay calm and just keep doing what they've been doing, that's what's got them to where they are."
Of his own form, Garcia added: “Last season was a period of transition and about settling in, I'd been at Rayo for three seasons. It's important to feel comfortable, fulfilled and to have the support of your teammates. Then you gradually have to make progress and try and help the team as well as you possibly can."