Sabrina Carpenter's fans must've been saying "Please, Please, Please" be warm water ... 'cause several posted on social media saying they got straight-up peed on by a fellow fan -- who unleashed her stream in the middle of the pit!
Here's the deal ... Sabrina took the stage at Chase Center in San Francisco Saturday night -- serenading the packed crowd at the arena.
While her show seemed to go off without a hitch, some fans in the pit said their night wasn't so clean ... literally, 'cause they swear a woman squatted down and took a piss right next to them.
Worth noting ... there's no video of anyone actually peeing -- but, these fans filmed the aftermath of the alleged bathroom experience, capturing a huge puddle staining the floor.
Everyone quickly moved away from it -- leaving a huge crater in the crowd. Fans could do the same if someone simply spilled a beer ... though it's a concert, and that's sorta par for the course. Urine in the pit ... a bit less common.
BTW ... this ain't just one or two fans making these claim -- a good 7 people were photographed holding up phones with the message "I Got Peed on in the Pit to See Sabrina Carpenter" written in big block lettering.
It's possible the fan just a got a little too excited and couldn't hold her bladder ... after all, she was waiting to see the newly minted 6-time Grammy nominee -- and, that's pretty dang exciting!
Still, next time maybe just find a bathroom ... or, wear a diaper like all the Swifties out there!