Jamie Carragher believes that 'world class' Liverpool boss Jurgen Klopp is the difference between the title contenders and struggling rivals Manchester United.
The former Reds defender hailed the impact of the German tactician, but admitted that the Premier League standings would take on a different complexion if Klopp was instead at the Old Trafford helm.
Ole Gunnar Solskjaer has come under increasing pressure after his side's stuttering start to the new season, leading to questions being raised over his long-term future.
Klopp had previously been linked to the hot seat at the fallen giants following his successful tenure at Borussia Dortmund, but reportedly turned down the role and later joined arch-rivals Liverpool.
The 52-year-old has since transformed the Anfield outfit, leading them to Champions League glory last term and just point behind Manchester United in a breathtaking title race.
And writing in his column for The Telegraph, Carragher labelled Klopp the difference maker between the two arch-rivals.
He said: 'I wrote two years ago that if United had appointed Pep Guardiola they would not be waiting long for the title.
'The same logic applies to Klopp. If he was United's manager, the Premier League table would look very different today.
'Let's not forget, even amid this vast improvement Liverpool still finished below United in 2016 and 2018.
'That sums up why for all the crowing about owners and executives and scouts the most important figure at any club is the manager.
'Get that right and everyone else looks better.'
Ahead of Sunday's showdown in Manchester, former Liverpool vice-captain Carragher also believes that the club's recent history will be separated into two categories - before Klopp's appointment in 2015 and after.
He added: 'The truth is, in the story of the modern Liverpool we will talk about the club before and after Klopp's arrival. The club's transformation quickened after he was unveiled in October 2015.
'Klopp led Liverpool to its current position by meeting a series of demanding but realistic targets one step at a time.
'You can spend all the hours you wish detailing the work of owners, chairmen, chief executives and heads of recruitment, but if you want to sum up what Liverpool possess that United lack, really it comes down to this – a world-class manager.'