Ahead of tonight's Champions League clash with Eintracht Frankfurt, Martin was asked about Real Madrid's home defeat to Celta Vigo on Sunday.
He said: "I watched the game, but it doesn't mean much. We were behind before, so it's always good to have a lead over Madrid.
"Villarreal are hot on our heels, but we're focusing on our job."
Martin also said: "(Hansi) Flick has given me a lot of confidence. Playing as a centre back requires focus on duels and building up from the back, but it's a position I know well.
"As a full-back, you have to press further forward; as a centre back, you have to focus more on duels and ball control."
He added, "I feel important. The coach gives me confidence, regardless of my position on the pitch. I don't consider myself more suited to one position than another."