The Dortmund boss believes his side will recover well for Wednesday's DFL-Supercup tie with Bayern Munich but was disappointed in their defending on Sunday
Daniel Sturridge, Dejan Lovren, Philippe Coutinho and Jordan Henderson were on target as Brendan Rodgers' side demolished the Bundesliga giants just days before their DFL-Supercup match with Bayern Munich.
Klopp admitted his side were second best in everything throughout Sunday's match, but expects his team to improve considerably once they have settled back into playing regularly after the summer.
"It was the wrong day and the wrong opponent for us in Liverpool," the coach told Ruhr Nachrichten.
"The first two goals we conceded, we didn't defend well. If you make mistakes like those we made, then you will lose against an opponent like Liverpool.
"Our preparation has thus far been relatively unproblematic. From now on we will rest for the DFL-Supercup. The rhythm will come, then the freshness will return too."
Klopp and his men will be looking to replicate last year's victory over Bayern in the pre-Bundesliga trophy clash, which will be played at their Signal Iduna Park.