Champions League referee implicated in match-fixing case
The case involves former Czech Football Association (FACR) deputy head Roman Berbr, who has been in custody over suspected match-fixing since October.
"Very simply, I need just one political thing, OK? You will understand. Josef Krula stopped by on Monday," Berbr said, according to the wiretap.
Krula is Sparta's sports manager and a former referee.
Kralovec, who answered that he did understand, came under fire after the game as he had notably refused to send off Sparta midfielder Martin Frydek for stepping on an opponent, despite calls from the video referee.
Sparta, who have lost a chance to advance from the Europa League Group H also comprising AC Milan, Lille and Celtic Glasgow, have denied any wrongdoing and said they want "thorough investigation" of the case.
Berbr was one of 19 people detained by police in October as part of an organised group in the match-fixing case, four of whom have ended up in custody.
He stepped down from his position as a result.
A 66-year-old former referee, Berbr held his post since 2013 and according to local media has been pulling the strings in Czech football for years.
Media have made allegations over Berbr in relation to corruption cases and bullying at the FACR, but he has never been charged.
His wife Dagmar Damkova, the first female referee in the Czech Republic, stepped down from a post on the UEFA referees committee following the charges.