It is one of the mysteries of Jürgen Klopp's final season at Liverpool that remains unsolved. Just how have the Reds played against Manchester United three times and failed to win even once?

The Anfield stalemate in mid-December saw a deluge of shots somehow fail to beat André Onana before the FA Cup and Premier League double-header at Old Trafford in March and April respectively saw more chances missed and even more chaos. Liverpool should have won all three matches and somehow ended up without a victory in any of them.

Manchester United, with three fixtures left to play this season, has a negative goal difference. It could yet find itself outside of the European places at the end of the campaign having now been overtaken by Chelsea.

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After finishing third last season — an achievement made less impressive by the fact that Liverpool faced a struggle that no one predicted — Erik ten Hag's side has regressed substantially. Just like when it finished second under Ole Gunnar Solskjær, last season was a one-off rather than a stepping stone, even if those with a vested interest in Manchester United doing well somehow didn't see that coming.

Speaking on The Overlap last summer as part of a preview for the 2023/24 campaign, Gary Neville was defiant. "Let's take United as an example," he said. "You've got Bruno Fernandes, Mason Mount, Casemiro, Christian Eriksen... I think Jürgen Klopp would swap his midfield now for United's."

Last summer, Liverpool overhauled its midfield department, losing Fabinho, Jordan Henderson, Naby Keïta and James Milner, and bringing in Alexis Mac Allister, Dominik Szoboszlai, Wataru Endō and Ryan Gravenberch. And while not all of the new signings have fully come off for the Reds yet, there is no disputing which side is in the best state.

Szoboszlai and Gravenberch still have much improvement to do but their ceilings are high and they are young enough to think that there could be big strides taken in the coming years. Manchester United's senior midfield roster, by comparison, is aging and past its best, even if Kobbie Mainoo looks like a real talent.

Fernandes has 15 goals and 11 assists this season, which is an undeniably good output level. But turning 30 in September, the Portugal attacking midfielder has seen his peak years come during a struggling period for the team.

Mount, who was of interest to Liverpool before he chose to move to Old Trafford, has shown very little yet to justify the $69m (£55m/€64m) price tag that he commanded having made just 13 appearances, while Casemiro and Eriksen have undergone a similar drop-off to Fabinho. On Sky Sports after the defeat to Crystal Palace, Jamie Carragher urged the latter to take a move to Saudi Arabia, though Casemiro still has another two years remaining on a mega contract signed when he arrived from Real Madrid.

As the summer edges nearer, there is an argument for Liverpool to dip into the market and sign another midfielder, even though Stefan Bajčetić will essentially be a new option for Arne Slot to use next season. At Manchester United, though, the question is whether there are any midfielders who definitely shouldn't be sold rather than trying to pick an area for refinement.

Would Klopp (or Arne Slot, as it will now be) swap his midfield for Manchester United's? Not a chance. For a fraction of the cost, Liverpool is the team that is clearly much better set up for the future.