The 2020 world champion was running inside the top six in the early stages of the 20-lap race at Sepang before he started to drop off the pace.
With three laps to go, Mir ran off track at Turn 1 and dropped out of the top 10 to 19th, which he later explained was down to him having no power in his right arm to brake properly.
Mir says this bout of arm pump – known medically as compartment syndrome – came as a surprise as he never usually suffers from it, but will now consider surgery in the winter ahead of his switch to Honda in 2023.
“It looks like I had an episode of arm pump,” Mir said after Sunday’s Malaysian GP.
“In the previous years here is a track that normally you can have a little bit because it’s quite demanding. But not like this.
“I couldn’t understand the pressure I was doing and I lost all the strength on the right arm. That’s what happened.
“It’s a shame because the team did a great job and the bike was strong, I was able to be strong.
“Then during the race I didn’t feel any drop on the rear tyre. I had a drop but not a super one.
“So, for one part I’m happy because we showed important potential at the beginning of the race. But then these things you can’t control [happen].
“What makes me sad is I didn’t see it coming, because normally I always complain about my back, or the neck, but I never complain about the arm.
“I want to see the doctor to avoid it happening again because I can’t allow this to happen to me again. It can’t be a reason to finish the weekend like this.
“Yes, seriously I think [surgery] it can be a good option. Honestly, if you put everything together and then we think about why we had this problem: we changed a front level at the beginning of the weekend because I suggested it.
“Then I had some stomach problems, which I don’t know, could make it worse. Maybe a little bit of everything is what caused this big problem.”
Mir says he considered retiring late in the race due to the arm pump issue, but wanted to see the chequered flag.
“From more or less half of the race,” he replied when asked when the problem struck.
“The last 10 laps were really a challenge. I was not able to touch the front brake and put pressure on it.
“There was a moment I almost thought to stop because it doesn’t make a lot of sense to ride like this. But I wanted to finish.”
