Manchester United manager David Moyes should start to rebuild his shattered club by ushering Juan Mata into his squad

David Moyes hasn't been able to get the best out of his players this season. Photo: PA

Manchester United manager David Moyes should start to rebuild his shattered club by ushering Juan Mata into his squad on Friday.

Reeling from a disastrous debut campaign suffering possibly its lowest moment with the midweek Capital One Cup semi-final defeat by Sunderland, Moyes has reacted by agreeing to pay a club-record fee for Chelsea midfielder Mata.

The Spain international is set for a medical before confirming his transfer in time to join his new team-mates for training over the weekend ahead of what seems certain to be his debut, against Cardiff at Old Trafford on January 28.

Ineligible for the remainder of United's Champions League campaign, Mata is tasked with trying to help his new club secure a top-four spot, having dropped six points adrift of Liverpool.

Yet, whilst hopes of retaining their Premier League title have disappeared, United could have a significant say in who does win it.

And it has not escaped Arsene Wenger's attention that Mata will strengthen a United side who may have already faced Chelsea twice but have matches against Arsenal and Manchester City still to play.

"It opens up again questions about the dates of this transfer window," said Wenger.

"Some teams have already played twice against one opponent and some others not.

"If you want to respect the fairness for everybody that should not happen.

"I can understand completely what Chelsea are doing. They could have sold him last week.

"They do not make the rules, but maybe the rules should be adapted a bit more for more fairness."

None of this will concern United, whose dreadful campaign has led to Moyes being savaged by fans who bombarded radio phone-ins on Wednesday night to express their concerns.

Others have been more measured in their assessment, acknowledging the squad left by Sir Alex Ferguson was flattered in the extreme by a 20th championship, achieved by a massive 11 points.

It has created a situation where everyone, inside Old Trafford and out, accepts a major injection of morale is required.

Former defender Gary Pallister insists Mata will provide that, and said: "He is a fantastic signing."

Speaking at the National Football Museum, where he helped launch an exhibition dedicated to the 125th anniversary of the Northern League, Pallister added: "He has great skill, great imagination, flair and goalscoring ability.

"A lot of people can't quite understand why he has not been in Jose Mourinho's team after being player of the year for the last two seasons.

"He is the kind of player Manchester United fans want to see. He has great imagination and can get people off their seats in anticipation of the things he can do with a football.

"We are delighted to get hold of him. Hopefully he can help lift Manchester United out of the spell they are going through."