The Royals took a 34rd-minute lead when Nicky Shorey’s free-kick was headed into the Wigan net by Sean Morrison to bag his first Premier League goal.
However, the Latics hit back when Gómez scored twice in the space of 10 minutes to reverse the deficit and leave Martínez’s men headed for three points.
But when Wigan goalkeeper Ali Al-Habsi fumbled a high ball into his own net, it seemed Reading would salvage a crucial point, before Gómez scored a late winner in the 92nd minute.
“We all saw today what Jordi Gómez is all about,” Martínez told BBC Sport.
“The crowd were quite vocal with him in the first half and other players would have tried to hide for the rest of the game.”
He added: “This is a game that will be remembered for a long time to come, it was a tremendous game of football to watch.
“In addition to the goal we scored we had another three clear cut chances.
“Obviously defensively we’re a bit disappointed with the goals we conceded, but we corrected that at the other end of the pitch.”
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