The Red Devils signed Maguire in an £80m deal from Leicester City in the summer transfer window after seeing off competition from Manchester City.
Maguire’s transfer to the 20-time English champions saw Maguire become the world’s most expensive defender ahead of Virgil van Dijk.
While Maguire was regarded as a solid Premier League defender, the Englishman arrived at Old Trafford with no Champions League or Europa League experience despite his lavish price-tag.
The England international has made a decent start to his Manchester United career, despite an error in a 2-1 loss to Crystal Palace.
Former Manchester City defender Richards defended Maguire’s start to life at Old Trafford.
“I really like Harry Maguire,” Richards told BBC Sport.
“I think the problem was the transfer fee and people are automatically comparing him to Virgil van Dijk because of the price. He is a tough centre-half, he makes crucial tackles.
“When things are going badly, he will be the one that people blame because of the money spent on him. We need to give him a full season before we start making decisions on him.”
Manchester United signed three players in the summer transfer window.
The Red Devils started their summer spending with the £17m addition of Swansea City winger Daniel James.
Ole Gunnar Solskjaer bolstered his full-back options with the £50m signing of Aaron Wan-Bissaka.
Manchester United then completed their summer spending with the addition of Maguire addition.
Solskjaer’s side are looking to finish in the Premier League’s top four this season to secure a return to the Champions League.
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