The Brazilian playmaker was arrested on suspicion of drink driving in the early hours of Christmas Eve in Liverpool city centre and has since been charged ahead of a court date on January 31.
Asked at a news conference after the game if there were any doubts about whether Firmino would feature against the Potters, Klopp said:
“No, because he was actually the best man in training.
“There was no chance to leave him out. No chance. He trained outstanding and we didn’t think about it.”
Liverpool started shakily and deservedly went behind to Jon Walters’s powerful near-post header, but responses from Adam Lallana and Firmino put them in front before the break.
An own goal from Giannelli Imbula and a fourth from Daniel Sturridge, who seized on a poor back-pass from Ryan Shawcross to score 56 seconds after coming off the bench, completed the rout and sent out a strong message to a watching Pep Guardiola ahead of Saturday’s clash.
‘I got a text message to say Pep Guardiola was at the stadium,’ Klopp, who saw the Catalan’s presence as a mark of respect, added.
‘I am not sure he has watched a lot of games in other (opponents’) stadiums.’
The win puts Liverpool six points behind Chelsea and a point ahead of City — a gap they could extend to four should they triumph in Saturday’s late clash.
‘It’s a special game — we are already looking forward,’ said Klopp. ‘It will be difficult for both teams but exciting.
‘It’s at Anfield which is good. They are a good side and we are not too bad.’