Bruno Fernandes has revealed the secret behind his star turn as a centre-back in Manchester United's dramatic FA Cup win over Liverpool: he used to play in defence for his youth team in Portugal.

United were left with only two defenders on the pitch in extra-time after manager Erik ten Hag had taken off Aaron Wan-Bissaka, Raphael Varane and Victor Lindelof as he tried to turn the tie around.

It meant that Fernandes dropped into defence alongside Harry Maguire as an emergency centre-back for the rest of a classic encounter as United came back to win 4-3.

However, the 5ft 10in midfielder revealed that he used to play there for FC Infesta Under-9s, a junior club in Matosinhos north west of Porto. His coach Sergio Marques used Fernandes as a centre-back in the big games, and let him dominate the midfield when the opposition wasn't as strong.

'I do what's needed to win games,' said Fernandes of the unusual switch. 'I don't mind. It wasn't in the plan. It was trying to go man-marking on the pitch, but I felt at moments I could jump on their midfielders and at moments, I could drop a little bit to help H (Maguire) because obviously, Liverpool have a lot of pace up front.

'(Cody) Gakpo came on and he was fresh. H hasn't played for a long time, so I was there to help him and the defenders to get a result. I don't mind, but when I'm far away from the goal, I can't get my goals and assists! But they can't score anyway because I was a centre-half in my early career, so I still got something from that.'

Fernandes has his critics but the 29-year-old's commitment is clear from a remarkable appearance record. Last season, the former Sporting Lisbon star played more minutes than any player in world football – 6071 across 70 appearances for United and Portugal. This season, he has played in 38 of United's 40 games so far.

Fernandes credits it to his family upbringing in the industrial city of Maia. He lived in a modest first-floor apartment in Gueifães, a district on the outskirts of town, with his father José, mother Virgínia, elder brother Rodrigo and younger sister Sara.

'I just have to be grateful for my father and my mum because they made me the right way, the strong way,' added Fernandes, who hopes to shake off a dead leg to be fit for Portugal's games against Sweden and Slovenia during the international break.

'They've been here for the last two games and they give me that extra energy, with my kids and my wife (Ana), they always take care of me.

'My wife does a great job at home to give me as much rest as I can. It's difficult when you have two kids at home and they want to play. My youngest one wants to play football all the time, but I get my rest, my naps, everything I need, because she's there to help me. Part of this record is my family.'

After a memorable win over Liverpool, Fernandes will lead United out at Wembley in the FA Cup semi-final against Coventry City next month hoping to return there for the final in May having lost out to Manchester City last season.

'We knew playing at Old Trafford we don't fear anyone,' he said. 'Liverpool are in a good moment but we never had the disbelief we couldn't win this game.

'The game got a little bit spicy and it was more special because it's an FA Cup game and if you lose, you're out. We know the rivalry between the fans we know how United fans wanted us to win the game to give us something to celebrate because it's not been great for us.

'We saw the draw and the reaction was the same as when we drew Liverpool because our goal is to get in the final. We won't celebrate anything before because we have huge respect for every team we play against.

'We know from the draw obviously we're playing a Championship team and not a Premier League team, but Wolves went out against them.

'We have to respect every team that comes here, because I remember two seasons ago we went out against Middlesbrough at home. So we have to respect them, give them the respect they deserve and give our best performance, as we did against Liverpool and with the same mentality.'