Victory means the Belgians face Spain in the quarter-finals, while the US follow co-hosts Canada and Mexico out of the tournament with elimination in the round of 16 after a thoroughly flat performance.
All attention pre-game had been on Balogun's place in the US starting lineup, after US President Donald Trump asked FIFA to review the striker's one-game suspension for a red card, and the governing body controversially obliged.
But Belgium's XI had a few surprises of its own, with Kevin De Bruyne and Jeremy Doku among the heavyweights benched. And coach Rudi Garcia's gambit proved inspired, with De Ketelaere grabbing an early goal to puncture the feelgood vibes in Seattle.
Malik Tillman grabbed one back from a free kick, but De Ketelaere swiftly restored Belgium's lead. A catastrophic piece of goalkeeping by Matt Freese and a late Romelu Lukaku goal left the Americans dead and buried.
FIFA's move to suspend Balogun's ban after he was sent off in the previous round against Bosnia and Herzegovina has been slammed by football fans, pundits and players around the world, but there were no such misgivings among the Seattle crowd.
A colossal roar greeted the stadium announcement of Balogun's name in the starting XI, vastly dwarfing the cheers even for US talisman Christian Pulisic.
The "USA" thunderclap then echoed around the stadium, utterly drowning out a small corner of chanting Belgium fans in the opening minutes.
But the American party was swiftly silenced. The majority of 67,000 fans fell silent in the ninth minute as De Ketelaere scored, easily tapping home from close range after Nicolas Raskin's cross evaded some lax defending.
It was the first time the Americans had conceded the opener all World Cup. With the atmosphere deflated, no immediate fightback was visible on the pitch either. The midfield was outgunned and the defense looked nervous.
On the half-hour mark, Balogun drew a foul on the edge of the area and whipped the crowd back to life. He waved his arms frantically as Malik Tillman -- fresh from scoring a free kick against Bosnia -- lined up the ball.
Tillman's shot deflected off the Belgian wall and span into the net, and the stadium shook.
Dream over
But the joy was again short-lived. In the 33rd minute, De Ketelaere leapt up to meet Leandro Trossard's cross and comfortably out-jumped an off-balance Tim Ream to score his second.
The US inched back into the game as the first half closed out, with Balogun blasting over from a long Tillman throw, then narrowly failing to catch a long ball, again from the Bayer Leverkusen midfielder.
US coach Mauricio Pochettino switched formation at half-time, sending Gio Reyna into the number 10 role and pushing Weston McKennie out to the right. The Americans resumed play with more intensity, pushing higher up the pitch.
But self-inflicted disaster struck in the 57th minute. Freese came out to collect a Belgium long ball, turned to evade the charging De Ketelaere, but then hesitated with his pass.
De Ketelaere jabbed the ball to Hans Vanaken, who made no mistake with an open goal from long range.
Pulisic limped off with an injury minutes later, and with him went the US dreams of reaching a first World Cup quarter-final since 2002.
His replacement, Sebastian Berhalter, flashed an ambitious shot narrowly wide in the 79th minute, and Balogun had a close-range effort saved soon after.
But Chris Richards handed the ball to Lukaku in stoppage time, and the veteran striker did not hestitate to seal the rout.
Source: AFP
--Agencies
