The Everton striker had gone 11 competitive games for club and country without scoring before finding the net twice in the second half of his country's 3-0 triumph in Bordeaux on Saturday.
Lukaku's place in the team had been questioned by some following the 2-0 defeat to Italy in Belgium's tournament opener, yet Chelsea forward Hazard insists his compatriot never let any criticism affect him.
"When a striker doesn't score, he tends to get criticism.
"But he can take it, he's mentally strong and I am sure he will be the difference for us in each game, I hope."
Belgium coach Marc Wilmots will hope the 23-year-old can fire them to victory again in the crucial clash with Group E rivals Sweden in Nice on Wednesday.