Lukaku spent last season at Goodison Park, scoring 15 goals in 29 Premier league starts, but returned to his parent club at the end of the campaign.
In a clip the fans could be heard asking: "Robby, can we get Lukaku?"
And Martinez abruptly told supporters the Belgian would be back at Goodison Park next season.
"Of course, of course we'll get him," the Spaniard replied with a smile across his face.
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