Brazilian news outlet O Globo said former Atletico Madrid duo Diego Ribas and Filipe Luis were among the players to test positive. Others were Chile international right-back Mauricio Isla, winger Bruno Henrique, forward Michael Delgado and defender Matheuzinho, the report added.
Last week, second division striker Philipp Hoffmann refused to play for his team Karlsruher SC after he had told the club his plans to join Union Berlin.
The pay-tv stations covering the game, Sky and DZAN, announced they would not be sending reporters to Budapest but instead would commentate on the game from Germany.
Finding suitable squad replacements appears to be just as stressful as dealing with contract extensions of vital players.
The weekend now kicks off on Saturday lunchtime with Alaves looking for their first point of the season when they entertain an always complicated Getafe, who are coached by former Alaves boss Jose Bordalas.
Real Madrid coach Zinedine Zidane was without Eden Hazard, Marco Asensio and Isco, but he produced a surprise by including Martin Odegaard, who spent last season on loan in San Sebastian, in his starting 11 and leaving Casemiro on the subs bench.
"The stadium has been designed to respect and preserve the heritage of the area, while bringing a long-standing semi-derelict dockland site back into productive use," added the spokesperson.
The 24-time Norway international follows Josep Martinez, Hee-Chan Hwang, Benjamin Henrichs, Lazar Samardzic and Angelino as the sixth new arrival of the summer transfer period.
Iago Aspas scored twice as Celta Vigo won 2-1 at home to Valencia on Saturday night.
Both sides had chances in the first half, but all shooting attempts were of low quality. Wang Shenchao was fouled in the penalty area in 42nd minute, but the Shanghai defender was offside beforehand.
Omar Al Soma (R, front) of Al Ahli Saudi FC vies with Farshid Esmaeili(L, front) of Esteghlal FC during the AFC Asian Champions League group A football match between Esteghlal FC of Iran and Al Ahli Saudi FC of Saudi Arabia in Doha, capital of Qatar, Sept. 23, 2020. (Photo by Nikku/Xinhua)