Saturday's stunning 4-0 win over Newcastle has Wigan on course to pull off another great escape from relegation trouble, and Whelan believes recent performances will have big clubs from around Europe eyeing up his Spanish boss.
"He's doing a magnificent job," Whelan told Radio Five Live's Sportsweek. "I've always said Roberto will go to one of the top clubs in Europe and when that time comes he will leave Wigan with my blessing."
Whelan said he is not keen to see the 38-year-old leave but he would accept Martinez's departure when it comes.
"He's just a brilliant manager and he will get one of the top jobs in Europe. I don't want to lose Roberto but it is inevitable he will climb the ladder," he said.
At one stage this season, Wigan lost eight matches in a row, and seemed near certainties for the drop.
But the Newcastle win put them three points clear of the drop zone going into their final two matches against fellow strugglers Blackburn and already-relegated Wolves.
Whelan insisted that even during the toughest times this season, he never had any doubts that Martinez was the right man to save them, and that the fans were on board too.
"(Managers) need support too," he said. "He got support from the chairman and he got support from the fans too. We've not had one fan crying for his dismissal and every fan in Wigan has been behind Roberto.
"Hopefully now we can stay in the Premier League for another season."
Source: PA
Source: PA