The Reds crashed out of the Carabao Cup last night at the King Power Stadium.
Liverpool were beaten 2-0 by Leicester thanks to goals from Shinji Okazaki and Islam Slimani.
While the defence took a big chunk of the blame, Klopp’s side were far inferior without Coutinho’s influence.
The Brazilian is still working his way back to full fitness and shone in a dominant first half for Liverpool.
But Klopp took him off at the break for Ben Woodburn and Leicester then took control.
The Liverpool manager accepts his defence were at fault and his team stopped playing such free-flowing football, although Coutinho was never set for a 90-minute run out.
“I know football long enough, and if you don’t defend these two situations well enough you give the opponent a chance to score - and that was obviously the case,” Klopp told talkSPORT.
“The first half was brilliant without scoring – unlucky in one or two moments I would say – but that’s how it is in football.
“If you don’t score you have to carry on and you will score in one moment.
“The second half it was clear we were not that fluent, because we took Phil off – as was the plan from before the game.”
Coutinho could start for Liverpool again when they head back to Leicester in the Premier League on Saturday (5.30pm).
Klopp will hope his star playmaker will be fit enough and ready for a full game.
The Reds are in need of three points after slipping up against Burnley at Anfield at the weekend in a 1-1 draw.
