Former Manchester United defender Gary Neville has described the team's midfield performance during their 4-0 defeat to Chelsea on Sunday as "embarrassing".
Jose Mourinho saw his side concede after just 30 seconds on his return to Stamford Bridge before Pedro's early goal was added to by Gary Cahill, Eden Hazard and N'Golo Kante.
United have heavily invested in their midfield area in recent seasons - not least with the world-record £89m signing of Paul Pogba - but Neville believes that the long-serving Michael Carrick still gives them the best "balance".
"I think that they got a little bit shoddy in the second half. It was embarrassing from Pogba and [Ander] Herrera. Kante just walked through them. They are the central midfield players. The first goal was just a joke, gifting a goal after 30 seconds," he told Sky Sports News.
"About three years ago there was a lot of talk about how Manchester United hadn't signed a defensive midfielder for years. They've signed about £180m of midfield players, [Marouane] Fellaini, Herrera, [Morgan] Schneiderlin, Pogba, I don't know what pair I can say is a good pair.
"Carrick actually looks like he still gives the most balance. The other four, there doesn't seem to be a pair between them."
United's defeat leaves them seventh in the Premier League table, already five points off the top four.
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