Catalan-born Jordi Gomez became only the second Spaniard to score a Premier League hat-trick when he produced a dazzling display to help Wigan beat Reading 3-2 at home at the weekend.
The victory came despite an injury crisis engulfing the DW Stadium and after a number of matches where 15th-placed Wigan played well but missed out.
"We couldn't get the points that I feel their performances have deserved and that's something we need to work on and we need to improve," Martinez told a news conference on Monday.
"It's important [to understand] that you're not going to be fantastic for 90 minutes in a game. I think it's important that you are in a position where you are capable of getting a positive result.
"I do feel that the performances have been a lot better than the points reflect and that's the next target of the next period of the competition."
Martinez will be without defender Ivan Ramis and midfielder Shaun Maloney for the match with Roberto Mancini's side after both picked up injuries against Reading.
Maloney's injury appears to be the worse of the two with a groin strain set to keep him out for an extended period while Ramis felt a twinge in his hamstring.
"With Ivan's injury we managed to catch it just in time before it got worse. He felt a twinge in his hamstring and we'll asses him to see how long he'll be out for," Martinez said.
The pair join captain Gary Caldwell, Ryo Miyaichi, Ben Watson, Albert Crusat and Antolin Alcaraz in Wigan's treatment room.
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