The atics were unlucky not to be awarded a penalty as Alan Hutton fouled Franco di Santo with the score at 1-0, but in truth a draw would have been harsh on Villa.
Speaking about the match, Martinez said: "It is frustrating but overall those decisions are a split second and you can understand why he didn't give it but you have seen them given. It was a difficult decision.
"But overall, we are more disappointed in the way we were careless in possession. We gave two balls away very cheaply and we were heavily punished. To concede goals that really changes things in games.
"With all the good things that we do we have to be a little careful in certain aspects of the game after getting punished and today we got heavily punished."
In an honest assesment of the game, Martinez refused to blame the lack of a penalty for his sides defeat. He added: "It's all too easy to look at possible decisions, obviously you need to get that next goal after going 2-0 down. There are key moments to do that, but overall, we want to improve and we want to get better.
"We have to make sure that we're a little bit more careful, especially away from home. I was pleased with the attitude and manner which we fought until the end. We need to regroup and get as many bodies back as possible."
In truth the Latics haven't competed for 90 minutes since August, and with Bolton, Newcastle and Fulham game son the horizon, that is very worrying for supporters.
