Romelu Lukaku and Eden Hazard both scored twice as Belgium strengthened their lead above England at the top of Group G by crushing Tunisia with a devastating attacking display.
While Roberto Martinez's side are not through to the last 16 yet, a win for England over Panama in Nizhny Novgorod on Sunday will see the Red Devils and Three Lions progress.
That would leave their meeting in Kaliningrad on Thursday to decide who tops the group and it is Belgium who currently hold the upper hand there, with their sparkling finishing in the sunshine at the Spartak Stadium leaving their goal difference significantly better off.
Belgium attacked from the off and took only five minutes to take the lead when Hazard was barged over by Syam Ben Youssef just inside the box and got up to send Tunisia keeper Farouk Ben Mustapha the wrong way from the spot.
Things quickly got worse for Tunisia when Ali Maaloul's heavy touch on the halfway line allowed Dries Mertens to nip in and release Lukaku, who found a perfect low finish.
The North African side, needing a win to reignite their own hopes of progress, gave themselves hope when Dylan Bronn got on the end of Wahbi Khazri's whipped free-kick just 109 seconds later.
But they could not compete with Belgium's vastly superior firepower and Lukaku gave the Red Devils breathing space once more with a dinked finish from a Thomas Meunier pass just before half-time.
Hazard added his second goal soon after the break, racing on to a precise Toby Alderweireld pass and rounding the keeper to fire home.
That made sure of the points, but Belgium were not finished yet. Substitute Michy Batshuayi, who also had a shot cleared off the line and hit the bar from close range, finally found the target from Youri Tielemans' cross.
Tunisia did manage a late consolation when Khazri swept home Hamdi Nagguez's cross but, unless Panama beat England, they will become the third African team to be eliminated, leaving Nigeria and Senegal to carry their continent's hopes in this competition.