Manchester United's biggest mistake of the summer transfer window may have been allowing Ander Herrera to depart the club.
The Spaniard joined United back in 2014 leaving Athletic Bilbao and became a crucial player.
Despite making 22 appearances in his final season at the club, he couldn't be convinced to stay and moved to France to join Ligue 1 champions PSG on a free transfer.
The MEN understand Herrera was offered over £200,000-per-week to stay at United but their failure to offer him fresh terms at the right time left a sour taste.
From the beginning of Ole Gunnar Solskjaer 's reign as manager, United have never lost a game in the Premier League when Herrera was on the field.
His only defeats under the Norwegian as a United player were against PSG in the Champions League and Wolves in the FA Cup.
The 30-year-old featured 16 times under the new manager's leadership, averaging the best points per appearance average in the entire squad (2.25) of players who appeared more than ten times.
It's evident that United's midfield has been missing some steel since his departure, Herrera averaged 1.7 tackles per game in the Premier League, more than any other player in the squad.
Only Ashley Young (1.8) averaged more interceptions than the Spain international. Furthermore, Herrera was United's most accurate passer from midfield.
United's form since his departure has been telling.
Defeat against Newcastle last weekend left the Reds just two points above the relegation zone, their worst start to a league season since 1989/90.
Fred, the £52million signing from Shahktar Donetsk, was given the chance to stake his claim to be Herrera's long-term replacement but his performance against the Magpies was pitiful.
He left United fans fuming with his display and former Arsenal defender Martin Keown branded him a joke.
The solution to their midfield woes might have been at the club back in May.
