Marczyński did not take to the start of the ninth stage of the Grand Tour yesterday, which saw riders complete a 158-kilometre route from Castel di Sangro to Campo Felice.

The Lotto Soudal team confirmed a team doctor had withdrawn Marczyński from the race for safety reasons, with further medical checks set to be conducted.

"No @TMarczynski at the start of stage 9 @giroditalia," the team wrote on Twitter.

"Tomasz is struggling with post covid neurologic symptoms: headache, insomnia, dizziness and coordination problems.

"Team doctor Maarten Meirhaeghe decided to pull him out for safety reasons and further examinations."

Marczyński reportedly contracted COVID-19 five months ago.

The Polish rider is not currently infected and tested negative prior to the start of the Giro d’Italia.

The majority of people who have contracted COVID-19 can make a full recovery within 12 weeks, however longer-term impacts of the virus have been reported.

Headaches and fatigue are among symptoms associated with long COVID.

Marczyński has expressed hope that he will be able to return to racing shortly.

"I'm sad to quit @giroditalia and leave my teammates, in the same time I'm really grateful to my team @Lotto_Soudal for supporting me in this moment," Marczyński said.

"Hope to be back in few weeks."

No positive tests for COVID-19 were recorded among riders prior to this year’s race, while a second round of PCR tests also saw no cases reported.

Riders are expected to be tested after today’s stage, as well as on the first rest day of the race tomorrow.

Organisers will hope to avoid a repeat of last year’s race, which saw the Mitchelton-Scott and Jumbo-Visma teams withdraw their riders from the race after positive tests.

Britain’s Simon Yates, who had been among the pre-race favourites, was among those forced to withdraw last year.

The 2020 race was held in October after the pandemic forced the event to be rescheduled.