Already qualified Belgium wrapped up first place in FIFA World Cup Group H after responding bravely to the setback of Steven Defour's first-half dismissal by rallying to beat South Korea 1-0 in Sao Paulo.
Marc Wilmots's team had booked progress with wins in their opening two games against Algeria (2-1) and Russia (1-0) and the only question at the Arena de Sao Paulo – where their lineup showed seven changes – was whether they would retain top billing in their group. This they achieved thanks to a determined reaction to Defour's sending-off which had its reward with Jan Vertonghen's 78th-minute close-range goal.
Belgium, who now face a round of 16 tie against the United States, had begun the third matchday requiring a solitary point to clinch pole, yet they started on the front foot. Dries Mertens lashed the ball over the bar after it broke fortuitously for the Belgium forward following Marouane Fellaini's flicked header and Kevin Mirallas's skip in the South Korea box. The SSC Napoli player also drifted a shot wide when well placed.
At the other end Thibaut Courtois twice excelled himself to keep the first half scoreless. First he turned behind Ki Sung-Yong's rasping drive from distance; from a similarly grounded position he blocked out a ball that deflected off defenders Nicolas Lombaerts and Mousa Dembélé under pressure from Son Heung-Min.
Belgium were reduced to ten men on the stroke of half-time, however, when Defour was red-carded for a challenge on Shin-Wook Kim. Myung-Bo Hong's men made the running early in the second period, with Keun-Ho Lee nodding dangerously over. Ki also had a headed opportunity while Son's cross-shot landed on top of the bar.
However, the European side continued to carry a threat through the pace of Mertens, Adnan Januzaj and Nacer Chadli, with the latter eliciting a save from Kim Seung-Gyu. When Kim subsequently saved substitute Divock Origi's powerful low strike, the ball rebounded for Vertonghen, Belgium's acting captain, to follow up and sweep home. Eden Hazard might have made it two, but the Red Devils already had their perfect record to take into the knockout phase.