The pair played together as young players for Real Madrid.
Along with Real Madrid, Garcia is also a former Benfica player and coach.
Ahead of tonight's Champions League tie between his two old teams, Garcia told Marca: “At that age, we were just kids and it seemed so far away, we didn't think about it.
"But as time goes by, you remember things and it became clear. He had that contagious character, he was always looking to motivate his teammates. He always found a way to push the group, to get everyone involved.
"Looking at him now, many of the things he did as a player fit perfectly with what we see him doing as a coach today.”
On Arbeloa's appointment, he also said: “It doesn't surprise me. Álvaro is very intelligent; he knows perfectly well what he's doing, what he's doing it for, and why. He's a very level-headed person, and the only thing that interests him is winning titles and succeeding at Real Madrid.
"We're already seeing changes, especially in the players' attitude. In the last match against Villarreal, I saw a team that wanted to play, to have the ball, to defend, that played with pleasure. That change is due to Álvaro, and after that match, I sincerely believe things are going to work out.”