Mahmoud El-Banna, the referee of the Zamalek-ENPPI clash, said he did not know there were victims in front of Cairo's Air Defence Stadium prior to kick-off on Sunday.
According to the health ministry, 19 people died after clashes occurred between the police and Zamalek supporters before the match.
The game went ahead as scheduled despite the tragedy, prompting many to scold the referee and Egyptian Football Association officials for declining to call off the match.
"It was very difficult for us to reach the stadium because of the large numbers of Zamalek supporters," El-Banna said in a television interview on Monday.
Ultras White Knights said they were heavily tear-gassed as many fans scrambled to get in the stadium.
"When I asked about the heavy tear gas, security officials said that it was used to disperse fans who want to enter the stadium by force," El-Bann added.
"Everything was going well on the pitch. Even when the supporters cheered for the martyrs, the players told me that the chants referred to old incidents.
"If I knew that there was any supporter dead, I would have immediately canceled the match."
Earlier on Monday, the EFA announced three days of mourning and a stoppage of all football activity in the country after the disaster.
Police claim they died due to a stampede, while the Zamalek Ultras White Knights said a criminal plot was pre-planned, blaming new security procedures that included a 'metal cage' at the stadium gates.
Investigations are still ongoing.
The match was open to the public, unlike most other games between Egyptian clubs since the killing of 72 people in Port Said in February 2012 in the country's worst-ever sport disaster.
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