The effects of Liverpool's trip to Qatar for the Club World Cup were felt in their narrow win over Wolves, according to Jurgen Klopp.
Jurgen Klopp accepts he may have "killed the winning mood" with his post-match team talk after Liverpool's 1-0 win over Wolves but said his side's performance left much room for improvement.
Reds players including centre-back Virgil van Dijk were critical of their own performances after a tight game against Nuno Espirito Santo's side, with the Netherlands international saying Liverpool "can do better", and Klopp echoed his captain's comments.
Liverpool have a 10-point cushion at the top of the Premier League going into their clash with Sheffield United at Anfield on Thursday, but Klopp warned that a repeat of Sunday's performance will not suffice.
"The game gave us a lot of space for improvement," Klopp said of the narrow victory over Wolves. "I told the boys what they could have done better immediately after the game, so maybe that killed the winning mood!
"We have to work on performances. We should not start lying to ourselves that everything is fine when it's not. We have to make sure we improve.
"I am really concerned about different things. I'd like an easy life, but I don't have it, unfortunately."
In Sheffield United, Klopp's men face a side who have lost just one of their away games in the Premier League this season, that defeat coming at Manchester City on Sunday with a 2-0 scoreline.
Liverpool emerged from a packed December schedule of nine matches with eight wins and a defeat, including a 4-0 league victory over second-placed Leicester City on the back of Club World Cup glory in Qatar.
Klopp said the effect of the Qatar trip were evident against Wolves and revealed that the tests his players have faced since returning from Asia have forced him into some difficult selection decisions.
"Everyone was like, 'wow', coming back from Qatar to play against Leicester like this," Klopp told reporters. "Yes, that was really good but that's how it sometimes is, and the knock came three days later this time. We played Leicester, Wolves and Sheffield United who, in the form table, are the three teams behind us - we are playing teams in really good shape.
"When it's really busy you have to make changes, but you have to try to make sure that the pieces on the pitch fit together. When we played Everton at the beginning of the month and made five or six changes we were sure this offensive line would click together.
"The focus is always on the next game."