After several weeks of chopping and changing, Manchester United head coach Ruben Amorim has seemingly settled on his preferred back three.

For the first time since arriving at Old Trafford at the start of November, the United boss named the same trio for the third game running against Arsenal in the FA Cup on Sunday. Just as he had against Newcastle United and Liverpool, the Portuguese chief tasked Matthijs de Ligt, Harry Maguire and Lisandro Martinez with lining up across the backline, and they produced arguably their best performance as a trio thus far.

De Ligt and Maguire were particularly commanding, with the former making a heroic clearance to deny Leandro Trossard in extra-time and Maguire heading and clearing away just about everything Arsenal threw at him.

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Both players have experienced mixed seasons until recently, but they are now benefitting from Amorim morphing United into a team that operates with a three-man defence. De Ligt arrived at Old Trafford having experienced the system for club and country while Maguire often shone in the same structure for England.

United strengthened their centre-back options by signing Leny Yoro and De Ligt last summer, meaning it was expected they would both be competing for the same spot alongside Martinez. At the time of their arrivals, United were operating in in a 4-2-3-1 shape under Erik ten Hag.

De Ligt was signed to add experience whereas Yoro was drafted in with an eye on the future. Both were considered statement additions but the capture of Yoro attracted far more positivity.

Former United centre-back Rio Ferdinand questioned the signing of De Ligt, saying: "He's had a lot of injuries, hasn't started many games over the last two or three years and Man United are spending £45-50million on him. Is he going to come into Man United and make a difference?

"I think it's a big ask for him and all eyes are going to be on him. Big pressure, big opportunity for him, but there's a lot of uncertainty I think with this signing because of his previous seasons with two big clubs not going as well as we'd have anticipated."

De Ligt experienced a shaky start but his most recent performances, aided by a run of consistency and being able to familiarise himself with two consistent centre-back partners, have been encouraging.

De Ligt has been signed for big-money throughout his career, meaning there was every chance he would make a difference to United's defence. His recent performances suggest he is on track to do so.