So, barring an unprecedented defeat to Panama tomorrow, England and Belgium look set to compete for top spot in their group when they meet later this week.
And Belgium, who wrap up Group G against England on Thursday, may confront fitness concerns with Lukaku, who had his right ankle worked on in the first half before coming off in the 59th minute with the result no longer in question.
Belgium will assess the fitness of all three players within the next 48 hours.
Belgium and Russian Federation are the joint top scorers on eight goals from their two games.
Belgium were dominant from the outset, taking a 2-0 lead inside 16 minutes through Hazard's penalty and Lukaku's fine finish.
Romelu Lukaku made it two braces in as many games and captain Eden Hazard also struck twice as fancied Belgium stormed past Tunisia 5-2 on Saturday to take a big step towards the World Cup knock-out rounds.
The Belgian fans had barely finished celebrating before Tunisia pegged one back.
And Hazard doubled his total in the 51st minute, scoring on an open net after he ran under a pass from Toby Alderweireld and worked his way around goalkeeper Farouk Ben Mustapha before finishing.
FIFA World Cup 2018 Live Score Streaming, Belgium vs Tunisia: Tunisia will look to end the barren and winless run for Arab countries at the World Cup in Russian Federation when they face a much-fancied Belgium side in Moscow.
Belgium were much the better team, looking unsafe on nearly every attack, but they were seriously aided and abetted by some ragged defending and non-existing marking from their opponents.
They haven't lost their second group stage game at any of their last seven World Cups.
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