Reims clinched promotion back to Ligue 1 thanks to a 1-0 home win over Ajaccio on Friday.
David Guion's side held a comfortable cushion at the top of the table but their promotion party appeared in danger of falling flat as they struggled to break the deadlock.
However, less than a minute after his introduction off the bench, Grejohn Kyei fizzed in a 76th-minute winner to secure the hosts all three points at Stade Auguste-Delaune.
With nearest rivals Nimes only able to draw 2-2 at Bourg-en-Bresse, Reims - who were relegated from France's top flight two seasons ago - have wrapped up the Ligue 2 title with five games to spare.
Jamais la cité des Sacres n’avait si bien porté son nom…. April 20, 2018
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