Andy Robertson has told talkSPORT Jurgen Klopp made it clear things had to change at Liverpool.
The Reds ended up with just a Community Shield to show for an underwhelming season where they finished fifth in the Premier League, missing out on Champions League football.
After competing until the very end in all four competitions the previous campaign, it was a huge drop off for Liverpool, despite the only summer difference being Sadio Mane departing for Darwin Nunez.
Early exits in all three cup competitions coincided with terrible league form, which was only patched up by a late seven-game winning streak.
That run was triggered by Klopp letting his players know they had to improve.
Asked what the manager’s message was to his stars over the summer, he told talkSPORT Jim White: “I think that message started six to eight weeks before the end of the season.
“We changed stuff and we were always looking to the next season, the message already started.
“But the pre-season will be a big one, we have to get it right in terms of fitness and get ourselves as ready as we can, and in terms of tactics.
“I’m sure we’ll be doing a lot of work to try and make us a better team and one that can compete for trophies.”
Robertson believes Liverpool will come good again and challenge Pep Guardiola’s treble winners. “City were a class apart from the whole league last season,” he added.
“We weren’t anywhere close to that. Obviously the last four, five seasons, we have been the team that has pushed them, we’ve been the team that has tried to compete with them, but this season they won it all.
“They won the treble and rightly so, they were the best team in Europe by a country mile and deserve all the plaudits they are going to get. But we can’t concentrate on other teams, we were below the standards we have set for ourselves and it is up to us to try and get back to that and if we do, I believe we can be successful again.”
When questioned about how anyone can knock City off their pedestal, Robertson insisted they would focus on themselves.
“We have to be back to our best and we believe if we are back to our best, we can compete with any team, but if we drop below those standards then we know we are struggling. This is what we have done this season – we dropped below the consistent standards we set for ourselves the last five, six years and we have been punished for it. We have to deal with that and try to make sure it doesn’t happen again.”