Two early goals from Victor Moses and further strikes from Shaun Maloney and Franco Di Santo sent Wigan out of sight before half-time and ensured Martinez's men claimed another notable scalp on their march towards safety.
Martinez said: "I'm extremely pleased because what we've shown today is a real clinical touch that we have lacked in the past. I thought the 4-0 lead was fully deserved at half-time and there is a real satisfaction that we saw it through.
"It was huge win today and we have two more huge games against Blackburn and Wolves. This result is fantastic for the fans but if we don't achieve our aim of staying in this league then it is going to mean nothing."