The former Chelsea goalkeeper was on top of the world as recently as last July, his fine performances steering Belgium to a third-place finish in the World Cup in Russia.
His joy was capped by a long-awaited move to Real Madrid as well as the FIFA The Best Goalkeeper award for his displays over the course of the past campaign.
But since moving back to the Spanish capital, where he previously starred with Atletico Madrid, Courtois has found things rather more difficult.
He has failed to show his best form during a desperately disappointing term for the Blancos, and seems to have lost favour with new coach Zinedine Zidane turning to Keylor Navas for his first game back at Santiago Bernabeu.
And if Courtois was hoping to impress Zidane, he certainly picked the wrong way to go about it on Thursday.
The goalkeeper was caught dallying in possession and could only slice the ball in the direction of Russia winger Denis Cheryshev, who gleefully converted to cancel out Youri Tielemans' early opener.
Belgium recovered from that blow, scoring twice through Eden Hazard to eventually stroll to a 3-1 victory.
But that did not stop Courtois feeling the full brunt of the internet's scorn, with schadenfreude-fuelled Chelsea fans particularly willing to mock their former hero for his mistake.
Courtois easily the most overrated goalkeeper ever. Should have never arrived at Madrid and should not have been best GK at the 2018WC. He’s the Belgian Joe Hart— Enrique (@un_diaz_) 21 de marzo de 2019
We all started taking the piss out of Courtois in the beginning for banter reasons but this guy is actually struggling lmao mistake after mistake— َ (@HazardEdition) 21 de marzo de 2019
Courtois doing what he does best...— William Hill (@WilliamHill) 21 de marzo de 2019
Conceding goals 😎 pic.twitter.com/KnCKG1e6fb
Chelsea fans watching Thibaut Courtois making another mistake like: pic.twitter.com/Y6HGg6Njmk— Goal (@goal) 21 de marzo de 2019