It has become one of the more regular observations of Arne Slot's still fledgling Liverpool tenure. And is given the Reds boss increasingly had little option but to think on his feet.

As was most recently seen in the Premier League visit to West Ham United last Sunday, the opposing manager has been showing a tendency for ripping up an established playbook when encountering the Anfield side.

"Until now, every time, a team lines up a bit different to us than all the weeks before," said Slot after Xabi Alonso, on his return to Liverpool as Bayer Leverkusen boss in November, opted not to start with a central attacker. "Managers change their gameplan when they come to Anfield or when they play us.

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"The good thing for us is that it's mostly also the first time that they play it, so you could argue if it's an advantage for us, but they feel that it's an advantage for them."

That Leverkusen were eventually dismissed 4-0 for only their third defeat in 18 months while West Ham were thumped 5-0, the change to long-honed methods clearly did Liverpool's opponents few favours with the Reds able to adapt accordingly.

Of course, Slot isn't averse to the odd unexpected tactical tweak himself, seen first with Ryan Gravenberch being shifted into a defensive midfield role at the start of the season and, later on, using Luis Diaz as a number nine.

That the Colombian started as the central striker when bagging a first career hat-trick in the win over Leverkusen and opening the scoring in the romp at West Ham, both games in which Gravenberch also impressed, underlines Slot's nous.

However, it seems likely Liverpool will know exactly what to expect when bitter North West rivals Manchester United make the short journey down the East Lancs Road for their blockbusting Premier League showdown on Sunday afternoon.

New United boss Ruben Amorim has shown little inclination of moving away from the approach of a three-man defence with two wing-backs that proved the bedrock of his success at Sporting Lisbon but has yet to truly find favour at United, with his new charges having lost five of their last six Premier League games as he seeks the right blend.

Indeed, it was because Slot's style of play at Feyenoord more closer matched that of Jurgen Klopp that Liverpool started leaning towards the Dutchman as their new boss when Amorim had been one of the early front-runners.

It has already been highlighted this week is the first in which United have had no midweek game following the Portuguese's arrival in November, allowing for extra time to work on the training ground.

Liverpool, too, have been without a fixture - their only such break from the last week in November until mid-February at the earliest - with the players having been given three days off before reconvening at the AXA Training Centre on Thursday.

With only the hamstrung Joe Gomez unable to train, Slot has an almost full-strength squad from which to choose although with Ibrahima Konate and Conor Bradley having only returned to full team training on Friday after both were sidelined for six weeks, it seems unlikely either will make the starting line-up.

And while Liverpool are odds-on favourites to compound the gloom of United - who have failed to score in eight of their last nine Anfield visits and have beaten the Reds only once in their last 13 Premier League meetings - skipper Virgil van Dijk is prepared for a difficult afternoon.

“Make no mistake, this will be a tough test," he said in the official Liverpool matchday programme. "We know that United aren’t where they would like to be in the league table and that they have had a difficult start to the season, but they still have top players so it is important that we are on it and focused from the very first whistle.

“We know what success is built on. Quality for sure, but also humility, sacrifice, work ethic and togetherness. If we keep that at the front of our minds always, then those are the things that will take us to where we want to be.

“The platform we have given ourselves throughout the opening months of the season is clear, but we have to push on from here now. We are not looking at the league table or counting points we haven’t won yet. We are focused only on the next game, the next challenge. Consistency is key, day to day and game to game."

And should Amorim attempt a surprise with his United line-up, Slot and Liverpool have already demonstrated they are ready to cope.