Antolín Alcaraz rose highest at the back post to head the decisive goal past Blackburn goalkeeper Paul Robinson in the 87th minute to move Wigan five points clear of the drop zone with one game remaining.
It capped a remarkable turnaround for Martínez’s side, who were bottom of the table in late March before a run of six wins in their last eight game, including victories over Arsenal, Liverpool and Manchester United lifted them to safety.
“It’s a great feeling because it was a difficult game,” Martínez told Sky Sports.
“It was a game which you could feel the tension and it was a cagey affair but our determination and ability to keep a clean sheet away from home is such a pleasing feeling.
“And then at the end of it, with what that win means [to stay up], it’s incredible. One game to go and we are eight years in the Premier League. It’s an incredible achievement.
“These players deserve so much credit. What we had to do in the last 13 games is a very tough, tough job.
“Today it was more than that. It was being mentally strong to cope with the occasion and what it meant.
“Of course everyone played on Sunday and we came into a game which had a lot more significance than should have been there.
“The players deserve a huge amount of credit to cope with that in the manner they did.”
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