While the UK government removed Brazil from its red list for travel on Monday, the national team travelled to both Venezuela and Colombia this month.
Those countries are still restricted when it comes to re-entry to England, with those travelling required to quarantine for 10 days upon their return.
An exemption was made for footballers, allowing their isolation to take place in a club bubble, leaving once per day to train or play, but issues remain for those with fixtures scheduled abroad.
However, speaking to reporters ahead of Brazil’s meeting with Uruguay in Manaus on Friday, the midfielder discussed the possibility of flying directly to Spain when their international duty ends.
“With all of what is involved, travel, I don’t know how much time we will have between one game and the other,” he said, effectively ruling himself out of Saturday’s trip to Watford.
“We will also need to quarantine, but the club is still studying whether it is better to go straight to Spain to play Atletico and quarantine there, without staying in a hotel in England.”
The Brazil squad left red-listed Colombia on October 10, which means the Liverpool pair would not need to isolate if they returned to the UK on or after October 21.
With the Atletico game not until two days prior to that, and the Reds’ next fixture against Man United being held on October 24, it is feasible that Fabinho and Alisson travel both to and from Spain separate from the squad.