Klopp started with his key quartet Philippe Coutinho, Sadie Mane, Roberto Firmino and Mohamed Salah for the first time last night but could only draw 1-1 at Spartak Moscow.
Coutinho cancelled out Fernando’s free-kick but Liverpool – despite creating a number of chances – could not force a winner.
The draw, Liverpool’s second in succession, leaves them third in Group E.
However, Klopp has no doubt about their chances of qualification for the knockout stages with four matches remaining.
“We are strong enough to qualify,” Klopp said in his post-match press conference.
“The door is open but we have to walk through. We can see a bit of light. We have to stay cool, work hard and we will be alright.
“The only thing is to go through the group and that is still possible for us.
“We would have won both games but didn’t, and that is our fault. There were a lot of good things, it was not a good result.
“It is a big question why we did not win. We were unlucky, there were good saves from both goalkeepers at the decisive moment.
“That is how football is – the only way you can change it is to do it again and do it again.”