LONDON • Manchester United's current squad is the most expensive ever assembled, with the world record purchase of Paul Pogba having taken their spending to more than £600 million (S$1.048 billion), according to research from the CIES Football Observatory.
The appointment of Jose Mourinho as manager in the close season sparked a new spending spree at the English club, with Eric Bailly and Henrikh Mkhitaryan joining £93.2 million-Pogba as the club's new signings.
United also secured Zlatan Ibrahimovic on a free transfer from Paris Saint-Germain, although the Swede's estimated salary of around £10 million a year makes him the highest-paid player in England.
CIES has calculated that it takes United's overall spending on transfers and wages over the £600 million mark - more than £160 million than they had invested this time last year.
Spanish club Real Madrid had previously been the most expensive in history at £429 million, with that figure having increased by more than £100 million to £550 million.
England's Manchester City are third on £530 million, having purchased John Stones, Claudio Bravo, Nolito and Leroy Sane, among others, this summer.
English clubs are heavily represented in the remainder of the top 10, with Chelsea, Arsenal and Liverpool all listed.
Tottenham Hotspur, Everton, West Ham United and Southampton also make it into the top 20, while last season's Premier League champions Leicester City are down in 27th on £114 million.
United, despite their big spending, lie five points behind arch-rivals City in the title race.
But Ander Herrera believes the deficit can be overhauled, with the midfielder pointing to how City overtook United to claim the championship four years ago despite trailing by eight points with only six games left of that campaign.
In 2011-12, Alex Ferguson's team led by eight points from Roberto Mancini's City yet the Italian's side won the championship on the final day.
Herrera admitted last Sunday's 1-1 draw with Stoke City at Old Trafford was painful, given United's dominance, but he remains confident.
He said: "When I was in Spain, I remember United being eight points ahead of City with only six games but they still lost that title. So in the Premier League, anything can happen.
"But we are very sad because we should have won this game. These are the kind of games we shouldn't draw at home because we played fantastic. But we can take a lot of good things from this game."
Following the international break, United play Liverpool and Chelsea in the Premier League and Fenerbahce in the Europa League.
Herrera admits these games are tough but is confident United will fare well.
"In football you never know," he said. "Maybe we go to Liverpool and create (only) two chances and yet we win the game. This is football and we have to accept that."
Mourinho's men also take on City in the League Cup at Old Trafford on Oct 26, having lost 1-2 - and been generally outplayed - when the sides met there last month.
But Herrera believes his team will be better prepared this time.
"We have a very good squad, we have shown that, and we can face every game in every competition," he said.