Oscar Piastri could be called up by McLaren for the Monaco Grand Prix as Lando Norris battles tonsillitis.

Norris struggled with the condition throughout the Spanish Grand Prix weekend, not helped by temperatures that soared into the mid-30s in Barcelona.

Early in the weekend, Norris’ conditions were put down to allergies, only for that prognosis to worsen as the event progressed.

Visibly unwell prior to the race, the 22-year-old was able to finish an impressive eighth after starting 11th.

Pleased with his young driver’s performance, team boss Andreas Seidl is hopeful that there is time to recover prior to opening practice in Monaco on Friday.

“I can’t thank him enough for battling it through, and he showed a great fighting spirit because, in the end, it enabled us to score these four points,” Seidl said of Norris’ Spainish performance.

“We obviously have a doctor involved in decisions like that [to allow him to race], and we would never risk the health of Lando, just to be clear on that as well.”

Following the race, Norris did not participate in the usual media briefings as he received medical treatment.

“Obviously [he] is not feeling well all weekend,” Seidl said when asked of his condition by Speedcafe.com.

“Your energy levels are low with tonsillitis, I think it’s called in English. He was suffering from it.

“It was a very challenging race today in the afternoon, especially in these hot temperatures as well, so he was pretty flat.

“We need to make sure he has some good rest in the next four days before we then go again in Monaco.

“I think with the medical support we are having as well, and with having the possibility now to rest for four days, I’m hopeful that Lando will be fit.

“But, as you know, we have different options in terms of reserve drivers prepared, which we will pull in case of an emergency.”

Should Norris prove unfit, it could open the door for Piastri to make his F1 debut.

McLaren is one of a number of teams that does not have an explicit reserve driver, but does have deals with Mercedes and Alpine.

That latter of those gives McLaren access to Piastri, in addition to the pool of Mercedes drivers it also has access to through its power unit deal.

“That’s something we would work out on short notice,” Seidl said when asked by Speedcafe.com if Piastri could get the call.

“Which of the options we will call, it depends on the availability, because not all the guys are always available because of other commitments for other racing series.”

Opening practice in Monaco gets underway on Friday at 22:00 AEST.