Belgium and Egypt played to a 1-1 draw in Group G on Monday after Emam Ashour had given the North African side a first-half lead.
Belgium were struggling to force an equaliser until the burly Lukaku entered the fray and made an immediate impact, holding off two defenders as the ball ricocheted off Hany and into the net.
"We saw the impact of Lukaku when he came on," Belgium coach Rudi Garcia said.
The striker spent much of the last year out of the team as he played only 69 minutes for Italian side Napoli last season.
But following his return for Belgium’s two friendlies in June, Lukaku has shown his worth.
He scored his 90th international goal in the 2-0 win over Croatia, and grabbed an assist off the bench in the 5-0 rout of Tunisia.
The goal against Egypt will not go down in the record books as his, but may as well have, such was his influence in it.
Lukaku is not fit enough to start games after such a lengthy spell on the sidelines, but Belgium will be hoping he can soon change from impact substitute to a place in the starting lineup.
"I’m happy he’s recovered, because Belgium doesn’t have another player like him," Garcia told reporters recently.
"We’ll have to manage him carefully. I know everyone wants to see him start, but we’ll take it step-by-step."
Lukaku does not have the pace of old, or the mobility, but rather the power and street smarts to bully defenders.
Charles De Ketelaere, who started against Egypt, does not offer the same attributes, while Dodi Lukebakio does not have much international experience. The other striker in the squad, Matias Fernandez-Pardo, is perhaps one for the future.
If Belgium can get Lukaku more minutes, their chances of a first World Cup trophy increase significantly.
They are next in action against Iran on Sunday before a final group game versus New Zealand on June 26. Both will be focusing on ways to nullify the threat of Lukaku.