Mohamed Salah tore his former side apart with a brilliant individual performance, scoring twice and setting up another two goals.
But Roma scored twice late on through Edin Dzeko and Diego Perroti to give them some hope of turning the tie around in Rome, while Liverpool suffered an early blow when Oxlade-Chamberlain was forced off with a knee injury.
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And after the game Klopp appeared to suggest the midfielder’s injury would rule him out for a significant period of time.
“Oxlade, it’s probably a really bad injury.
“If we can say that already before the scan, that’s never good news so that means for us it’s a massive blow, of course.
“We have still a few very important games to go and the squad doesn’t get bigger in the moment, so we obviously need to be creative in the next few games.”
Oxlade-Chamberlain was taken off in the first-half (Reuters) (REUTERS)
But the Liverpool manager insisted he was attempting to stay positive after an impressive win which leaves his side firmly in the driving seat.
“For a long time it was a perfect performance,” he added.
“We made defensively one mistake. Penalty is not a penalty but that is the situation and now it is 5-2. Of course we would have been more happy with 5-0 or 5-1 but 5-2 is a fantastic result. We go there and try again.
“We had all these runs behind, it changed the game completely and they couldn't cope with that. We scored these goals and could have scored more.
“That is all positive, although at this moment it doesn't feel all positive because they scored these two goals but tomorrow I will see the really good part of the game.
“It is absolutely better than I thought before the game but at the moment of course we worry about a little mistake.”
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