Gareth Southgate's players have expressed their readiness to leave the Czech Republic tomorrow or Bulgaria next Tuesday, if any racist chants against them are issued during the Group A topped by England comfortably, in the Euro 2020 qualifiers.
The second match at the Vasil Levski Stadium in Sofia is more susceptible to such chants, as its stands were partially closed after chants during the same Kosovo qualifier in June.
The English faced racist chants during their 5-1 win in Montenegro.
"We've had several encounters since we arrived," said Chelsea striker Thami Abraham, 22, who has also been racist in England after missing a penalty against Liverpool at the European Super Cup in August. "If the chants are repeated, we will talk to the player in question. If he is not happy, we will leave the pitch together," the captain said.
Southgate, who led England in the summer of 2018 to the World Cup semi-finals in Russia, said England would respect the three-step UEFA protocol, first notifying the referee to send a message to the fans, then suspending the game temporarily if repeated insults and cheers, and finally stopping the game once Could not be completed under normal conditions.
In return for recalling young players such as Abraham, Mason Mount and Vecchio Tomori from Chelsea, Southgate kept a number of members of the 2018 World Cup squad out of his calculations this time, such as Jesse Lingard (Manchester United), Dale Alley (Tottenham) and Kyle Walker (Manchester City).
England have four full wins and are three points ahead of the Czech Republic, who played less, meaning a repeat of their big 5-0 win would put them in the continental finals next summer.
Despite the brilliant offensive of Harry Kane, Raheem Sterling and youngster Gaydon Sancho, the recent 5-3 win over Kosovo showed defensive flaws for Michael Keane (Everton) and new Manchester United player Harry Maguire.
Before their Group B clash with top-of-the-table Ukraine in Kiev on Monday, Portugal host Luxembourg looking for a third successive victory after scoring nine goals against Serbia and Lithuania, making up a slow start and two draws against Ukraine and Serbia.
The five-times World Player of the Year, Cristiano Ronaldo, Bernardo Silva (Manchester City) and Joao Felix (Atletico Madrid) are counting on the continental champions.
Portugal are five points behind Lithuania's host Ukraine but have played less.