A 1700 rated player just beat a 2700 rated player in a FIDE rated rapid chess game.

A 15 year old player rated 1781 just beat a 22 year old player rated 2774 in the first round of a tournament (Nex in Chess Classic). The name of the young winner? Praggnanandhaa Rameshbabu. Although some of his ratings are higher, his rating in the format played (rapid) is below 1800 meaning the win against Duda is technically a humongous upset. I assume this is the lowest rated player to ever beat a 2700 (although I'm not sure if some other edge case has happened). I doubt the nearly 1000 point gap is a record though.

Can you think of any upset in FIDE games that have such a huge gap? What are other cases of 2700 falling to lower rated foes? Is this the proof rapid isn't real chess?

It only proves that he didn't have an up to date rapid chess rating.

He has been a Grandmaster since 2018. His FIDE rating for classic chess is 2608.

https://en.wikipedia.org/wiki/Rameshbabu_Praggnanandhaa

He also beat Karjakin, another former prodigy.

Here is the game against Duda:

Thanks for the insightful post! With this inspirational upset, I am confident I can beat Magnus now!

A 1900 beat Alireza Firouzja (2759 FIDE) in a FIDE-rated game last year, no?

And unlike the example given above, this really was a 1900 player... not a GM with an obsolete rating.

rating means nothing. it holds some weight if you all start at 0 and are in a contained setting but to think anyone of knowledge cant beat anyone else at any given time is simply obtuse. common, certaily not but impossible?  ???doesnt surprise me a bit.