International Friendly: Belgium v Tunisia
Leekens has managed his home nation twice, with the most recent spell ending in 2012, and he will hope his knowledge of the current squad can help the African nation cause an upset.
After qualifying for their first FIFA World Cup in 12 years, Belgium travel to Brazil as one of the favourites after impressing throughout qualifying and possessing a squad brimming with talent.
Even though striker Christian Benteke will miss the tournament through injury, coach Marc Wilmots still has a plethora of attacking options to choose from, with Romelu Lukaku making his claim for a starting role with four goals in their two recent warm-up matches.
Axel Witsel impressed in the centre of midfield during the 5-1 win over Luxembourg and 2-0 victory against Sweden, leaving the 25-year-old feeling positive heading into the final preparation game.
"The team is ready," Witsel told Het Nieuwsblad. "In the main, everyone is serene.
"There is no nervousness. We know what we can set ourselves without putting any extra pressure on."
Algeria are first up for Belgium at the World Cup in Belo Horizonte, but before that is the clash with their neighbours Tunisia.
And Wilmots will be wary as Tunisia should not be taken lightly, having only lost twice in their last 12 outings and beaten South Korea 1-0 in Seoul last week to show that they are no pushovers.
That win came in Leekens' first match in charge since being appointed in March and he is relishing his return to Brussels this weekend.
"I come to Brussels as a proud Belgian," he said.
"The dream (of reaching the World Cup) has become a reality for the whole country.
"I am glad that I have contributed to that, (and) am looking forward to seeing many friends."
With only a week to go before the tournament in Brazil starts, Belgium will be keen to avoid any injury scares, although Wilmots is likely to play a strong side to keep the side's momentum going.