The 22-year-old Gunners academy graduate completed a blockbuster move to Monaco this summer for a fee of up to £35million, and started with a bang, scoring in his second appearance, a 2-2 draw against Lorient.
However, third time out against Nice in the Derby de la Cote d'Azur, Balogun's deadly touch that made him one of football's most exciting young strikers last season went missing.
The USA international twice missed from the penalty spot in a scoreless draw, and will be left with what's certain to be a sleepless night.
Last season for Rennes under Will Still, Balogun put himself on the world stage with 21 goals in 37 Ligue 1 games, and six of those efforts were from the spot.
But against Nice he looked like he'd never taken a penalty before, with the first effort struck hard, but barely off centre just to Marcin Bulka's right in the 12th minute.
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Later in the 55th, with an opportunity to atone from his earlier poor effort, Balogun did exactly the same again, with Bulka's only chance of not saving it being if he went the wrong way.
The Swiss goalkeeper went on to cap off a man of the match performance, setting up the platform for a stunning stoppage time winner from former Chelsea man Jeremie Boga away at the Stade Louis II, further compounding Balogun's misery.
Arsenal let the striker leave during the summer with his path into the first team clearly blocked by Gabriel Jesus, and also Eddie Nketiah.
Not only did Balogun grow tired of waiting for Mikel Arteta to give him a shot, but Gareth Southgate too, with minutes for the Three Lions senior squad not coming despite his Ligue 1 heroics.
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Having appeared for England's youth teams at all levels, Balogun has since switched to his US birthplace, and has begun with two goals in four games.