In a statement, the tournament organisers of the St Petersberg Open said Querrey did not open the door for a doctor's visit on Monday and the family left the hotel next day without informing the reception.
American Sam Querrey was placed in quarantine by the Russian authorities after returning a positive COVID-19 test but the former Wimbledon semi-finalist left the country on a private plane, organisers of the St Petersburg Open said on Thursday.
The tournament organisers said Querrey, his wife and baby son tested positive for the novel coronavirus on Sunday, a day before the main draw started.
The world number 49 was withdrawn from the competition and the family was asked to isolate together at a hotel.
In a statement, the tournament organisers said Querrey did not open the door for a doctor's visit on Monday and the family left the hotel next day without informing the reception.
Men's tennis body ATP on Wednesday released a statement to its players saying a "serious breach of protocol" had occurred at the tournament, but did not name Querrey.
"As Querrey told the ATP representative, he flew out of Russia on a private jet," organisers, Formula TX, said in a statement.
"The ATP representative passed on this information to the tournament management after the doctors made a repeat abortive attempt to examine the family.
"The tournament organising committee has done it all to ensure the safety of the players, the ATP representatives and all the services of the tournament. It is the power of the ATP to evaluate and assess the actions of the player Sam Querrey."
Querrey's representatives did not immediately respond to a request for comment.