The Latics carved out the better opportunities and Arouna Koné tested Spurs goalkeeper Brad Friedel with a low drive in the 29th minute which was pushed wide, before the American also denied Shaun Maloney.
However, Wigan took a deserved lead in the 55th minute when Ben Watson forced Maloney’s corner over the line despite Friedel’s best efforts to stop the midfielder’s shot.
Spurs did come close when Steven Caulker’s goalbound effort was headed off the line by James McCarthy, but the visitors clung on for their second victory in three seasons at White Hart Lane.
“The result is good enough to make you feel really pleased,” Martinez told BBC Sport.
“But today it was more than that it was the performance. Some people might see the result today and think we hit them on the break and that we were lucky, it wasn’t like that at all.
“We created three of four very good chances from open play and then we scored.
“The performance was more pleasing than the result today. It was a perfect performance.”
He added: “I was worried. When you play well you need do take the lead. But I knew that if we could keep our concentration we could repeat the performance. It wasn’t a fluke.
“We needed a team performance and we got that. We knew it would be different after the break, Tottenham had to come at us.
“But the way we handled what we had to do in different parts of the game shows an incredible winning mentality.”
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