Club America and Santos Laguna are rivals, so when you swear to never wear the colours of your fierce opposition, the fans don't forget. That's if you don't want any backlash.
Marchesin, however, decided to leave Santos Laguna in December and joined Club America soon after making that promise.
Before the two sides faced each other in the Copa MX, Marchesin told the media he hoped for a warm reception when he returned to Santos.
He didn't get it, of course, and Marchesin was inevitably subjected to relentless abuse.
At half-time, Santos fans decided to shower their former goalkeeper with fake bank notes as the 28-year-old made his way off the pitch.
Santos would go on to win 2-1 with a 94th-minute winner as well, making the day a pretty terrible one for Marchesin.
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