Martinez's men built on last weekend's first home success of the season against West Ham with another three points in north London as Ben Watson snatched a 56th-minute winner.
The Spanish manager praised the determined mentality of his side and says he could not have asked for more from their display.
"It was a perfect team performance," Martinez told Sky Sports.
"That's probably the most pleasing aspect, not the result - because obviously that's what we wanted - but the manner of the result. The performance was as good as it gets away from home.
"I thought the concentration of every player was magnificent and more than anything the mentality.
"To win at home then come here and show that intent of wanting the three points is probably the most pleasing aspect of this game.
"It's important that we keep creating chances and showing that team mentality of keeping a clean sheet."