Liverpool were without a number of first-team players for the City game. For some players, it was a case of resting after the World Cup, while the likes of Firmino and Trent were expected to start.
"Bobby in the last session [before the City game] felt something and we had other problems with Alex Oxlade-Chamberlain set to start and then he got ill two days ago and this morning he was fine," Jurgen Klopp said after the game.
"We thought Trent would available but then he got ill. Virgil trained today and yesterday completely normal and should be ready for Monday. But we have to see who gets the virus until then."
"Konate will be back next week."
James Milner left the pitch after suffering a knock in the first half.
"Millie is only a little thing, he felt something and we wanted to make sure it's not getting worse. It's maybe a hamstring, I don't know," Klopp added.
Bobby Firmino did not make the squad as he picked up an injury before the game, Klopp said.
"Not a big one but big enough for this period," he said.
