Jack Harrison scored an equaliser at the 12 minute of the match. Premier League 2020: Mohamed Salah's Hat-Trick Guides Liverpool to Victory Over Leeds United.
Robertson featured in the game but Cooper didn't as Liverpool and Leeds United played out a 4-3 scoreline.
He failed a late fitness test prior to the Merseyside trip, Cooper's defence missing his leadership at the back.
"I'm happy to have Mo Salah on the team and that he scored a hat-trick in the first official match of the season".
"Without fans, it's so tough, especially at Anfield.
They made our night hard tonight but I think their night was even more hard because of the way we played", the goalkeeper said.
"The players were calm, they played a serene game and went into it confident".
"There were periods when Liverpool dominated and there were lots of periods where the game was even, in some moments we were able to be superior".
"I scored a penalty in the Champions League final, so it was a little bit easier, especially with no fans".
Rodrigo has been capped 23 times by Spain, is a proven marksman at the highest level with eight goals for the national team as well as impressive records at elite clubs in Valencia and Benfica.
Despite two of Salah's goals being penalties, Reds boss Jurgen Klopp said the former Chelsea man completely deserved them and wishes to see him have more performances like that.
"He was top in one-on-one situations, played football. He is a very special player", said the Liverpool manager of Salah.
Salah will hope to add to his tally when he faces his former employers at Stamford Bridge next Sunday.