The reigning world champion had just gone to the top of the order around 15 minutes into the opening session at Jerez on Friday when he was flicked from his bike at the final corner having touched a damp patch.
He got back onto his bike and rolled it into pitlane, but was seen visibly winded having taken a knock to his groin area.
Quartararo made it back out for the end of FP1 and went on to top the day outright after going fastest in FP2 by 0.201s.
However, while it looked like he’d injured himself in the crash, Quartararo revealed after practice that he injured his groin when he jumped back onto his bike after the spill and got caught on the fuel tank.
Asked how he was after Friday’s running, Quartararo said: “Sore, I had a tough five minutes after the crash.
“But let’s say the pain is getting lower and lower, but I couldn’t breathe in one moment.
“It was myself [that caused my injury]. It was not even the bike. We put something new on the fuel tank and when I jumped on it [I hurt myself].
“I felt a little bit stupid because I crashed and did nothing.
“But when I took the bike and jumped on it [that’s what hurt]. So, maybe it was better to lie [and say] that it was the tyre – but I have to say I was stupid.”
Quartararo’s FP1 session after that crash was a bit scrappy, with the Yamaha rider making several mistakes on flying laps in quick succession.
But he says this was simply down to him not having a great feeling on the medium front tyre and he preferred to avoid any more crashes.
“Was nothing strange, just pushing and at the end with the wet patches I had one crash,” he added.
“Then I had one moment I braked too late and with the medium front I felt super bad because I felt there was basically no support. I felt the tyre was moving a lot and I didn’t want to take any risk and try to turn and crash again.
“So, I preferred to go straight and one moment I made a mistake shifting into fourth gear when I had to go to second.”
Overnight rain on Thursday led to the Jerez circuit retaining some damp patches for Friday’s practice despite the dry conditions, which caught several riders out including Quartararo.
Marc Marquez also crashed on a damp patch at Turn 8 while he cruising back to pitlane, with Quartararo admitting he hopes something is done about that area for Saturday as it is “quite dangerous”.
“Normally here at Jerez on Friday it’s super tough, so I was quite surprised because normally every Friday from our side we go not so great and today we made a good step,” he said.
“Even on FP2 there was some wet patches at Turn 8, and it’s not a good place to have them.
“So, I hope tomorrow even if it’s dry that someone really goes with something to dry it because to be honest it’s a place where it’s quite dangerous [to have a damp patch].
“The last corner it’s slow, but at Turn 8 you can have a big crash from the front or from the rear. So, it was a bit tricky.”
