Santon shone in their 5-0 win over Chievo on Sunday.
Spalletti said, “If we can squeeze our way into this position, it means we are doing great work. People act as if I make my line-ups by dropping players, but rather I pick those who are in the best condition, not drop those who are in the worst shape. When everyone is this strong, nobody is dropped.
“We knew Davide Santon well and he is a player with great quality, effort and versatility. Obviously, he does better and feels more confident in a position that suits him, then he will perform better."
Next up for Inter, they go to Turin for a Scudetto showdown with third-place Juventus.
“It's going to be extremely tough for us and we must get straight back to work, focusing on the things we know now and doing them to our best."