Jurgen Klopp believes the drop-off in form from his Liverpool stars since their rousing win over Manchester City undermines their claims to be world-class performers.
Liverpool dished out a first Premier League defeat of the season to Pep Guardiola's Premier League leaders in a thrilling and relentless display on January 14.
But that 4-3 triumph has been followed by a league loss at Swansea City and an FA Cup reverse at home to West Brom — the two bottom sides in England's top flight.
Liverpool's capacity to produce high-level performances on a consistent basis has been called into question, and the former Borussia Dortmund head coach challenged his men to relocate their best form for Tuesday's trip to Huddersfield Town.
"These boys, we know potential-wise are world class. But real world class is to bring it on the pitch again and again and again," he told reporters.
"We need to find out whether it's a misjudgement of the City game. I don't think so. But if it was, that needs to be finished.
"I don't think so. But if you want, since then our offensive positions didn't defend as well as then, for example. That's the truth."
Liverpool's tireless pressing from the front against City won deserved plaudits, but familiar defensive frailties were on display during their first-half collapse against West Brom.
"You need to defend really in a compact formation. We were not compact. That's the problem," Klopp explained, before confirming he hauled his squad in for a video debrief after the fourth-round humbling.
"In the video room, I showed the boys where we could have reacted much better.
"If we get back to defending when everybody is responsible, then we'll get back to defending better.
"That's why we showed the boys. It wasn't about blaming a player. It was about showing what really happened, because players probably won't look back at a game and think 'oh, that was it'.
"They will try to ignore it, and this time I didn't want to give them the opportunity to ignore it."
Liverpool lie fourth in the Premier League with 14 games of the season remaining, two points above Tottenham. Mauricio Pochettino's fifth-placed side visit Anfield on Sunday.