Dylan Bronn and Wahbi Khazri scored for Tunisia.
Belgium leads the group ahead of England’s Sunday match against Panama.
[ MORE: Latest 2018 World Cup news ]
Romelu Lukaku led an early break that led to a Thomas Meunier shot collected by Tunisian keeper Farouk Ben Mustapha.
Eden Hazard won a penalty in the fifth minute, just inside the 18. He converted the chance low and to the right of Ben Mustapha.
Ben Mustapha was fortunate when Hazard’s 12th minute shot of a terrific Lukaku pass was substandard.
Lukaku then scored a beauty in the 16th minute, sent into the 18 by Dries Mertens, when he clinically slid a shot inside the far post.
Tunisia got a surprise answer a minute later, with three goals gracing the games first 18 minutes. Bronn turned a free kick past Thibaut Courtois and into the back of the net.
[ LIVE: World Cup scores ]
Belgium was knocking on the door for most of the half, and a wobbly Kevin De Bruyne missed Lukaku with a stoppage time cross which should’ve led to a third.
Lukaku got his third courtesy of Meunier a moment later.
Hazard scored his second after the break, and Youri Tielemans assisted Batshuayi’s marker to round out the scoring for Belgium. Ex-Sunderland man Khazri scored late for Tunisia.
— OptaJoe (@OptaJoe) June 23, 2018