Jurgen Klopp believes "slapstick" mistakes have left Liverpool in a position where it will be almost impossible for them to qualify for the Champions League through finishing in the top four of the Premier League.
Liverpool's 1-0 win over Wolves on Tuesday morning leaves them five points adrift of fourth-placed Chelsea with nine games to go.
The champions' disappointing defence of their Premier League title has been hampered by injuries and haphazard play at the back.
Centre-backs Virgil van Dijk, Joe Gomez and Joel Matip are all long-term absentees while Jordan Henderson, who has often played in a makeshift role at the heart of the defence, has been sidelined with a groin injury.
The lack of a settled line-up at the back has contributed to Liverpool committing more errors leading to goals (9) than any other team in the division.
And, with Chelsea unbeaten in 10 league games since Thomas Tuchel replaced Frank Lampard as coach, Klopp does not see the Reds reaching Europe's elite club competition via what is typically the most achievable route.
Speaking to Lothar Matthaus in an interview for SportBild, Klopp said: "The opponent usually doesn't need a lot of chances against us because we make big mistakes, insane ones that can almost be described as slapstick.
"On the other hand, we create a lot of chances. In the 'expected goals' we are still second behind Manchester City in the Premier League, but far from them in the ones we actually scored.
"This problem has been going on throughout the season.
"I like to be an optimist, but in the league it is almost impossible to qualify [for the Champions League] in the competition for the places that we have.
"At Tottenham, Gareth Bale is now playing again, and they are also in the running. Plus City and Manchester United, who are far away. Chelsea is on the rise.
"Reaching Champions League qualification through the league will be difficult, we know that."
Klopp also cast doubt on Liverpool keeping their place in the Champions League by lifting the trophy this season.
Liverpool are through to the last eight having comfortably seen off RB Leipzig, and they won the competition under Klopp just two seasons ago.
But asked about the possibility of them regaining the European title, Klopp replied: "You don't usually win the Champions League itself in a year with injury worries as big as we have."