On Sunday afternoon, Ronald Araújo was throwing himself into challenges against Brighton, at one point even tackling the ball with his head while lying on the floor. A few hours later, Trent Alexander-Arnold was watching Federico Valverde play at right-back for Real Madrid, before Denzel Dumfries replaced him. Trent eventually got onto the pitch in stoppage time.

It's quite a turnaround for a player who was once considered one of the best right-backs in world football. A local lad, Liverpool's vice-captain and widely expected to become the club's next captain, Trent now finds himself third choice at Real Madrid, having played just 52 minutes across their last five matches.

And having watched him throughout his Liverpool career, I can't say I'm particularly surprised.

When José Mourinho returned to Madrid, one of the first things the club did was sign Dumfries from Inter Milan. That immediately raised questions for me. Mourinho already had Trent, so why did he feel the need to sign another right-back?

People will argue that he wanted competition for places, which is fair enough. But if Mourinho had been convinced by Trent, he could have started him and used Dumfries as his understudy. Instead, the Dutchman was preferred for much of the early season, and more recently Mourinho has turned to Valverde, a midfielder by trade.

For the best part of 25 years, Mourinho has built his teams around being defensively solid. I don't see him suddenly changing that approach to accommodate a right-back who struggles defensively. In my view, Trent will need a change of manager if he's going to establish himself at Madrid.

Why Liverpool's system suited Trent

None of this takes away from what Trent achieved at Liverpool. He was an exceptional attacking full-back, one of the most creative players in the team and a huge part of Jürgen Klopp's success. But I never considered him a particularly good defender, and Liverpool had a system that allowed him to flourish despite those weaknesses.

It wasn't deliberately built around Trent. Liverpool got an enormous amount of their creativity from both full-backs, with Trent and Andy Robertson providing the width and attacking quality that other teams might expect from their midfielders.

Jordan Henderson, Fabinho, Georginio Wijnaldum and James Milner were excellent footballers, but the main strength of that midfield was how it was set up and the work they put in. They covered enormous amounts of ground, protected the full-backs and allowed them to attack without leaving Liverpool constantly exposed.

Roberto Firmino also played a big part. He wasn't your typical striker, regularly dropping deeper to link play and create opportunities. With creativity coming from Firmino and the full-backs, Liverpool didn't need their midfield to be the primary source of chances.

Madrid have different players with different responsibilities. Jude Bellingham, for example, is one of the best number 10s in world football. He works hard, but you don't want him constantly tracking back to double up with his right-back. You want him as close to the opposition's goal as possible.

That's where Trent has a problem. When he's isolated one-on-one against a winger, particularly someone with pace, he can find himself in serious trouble. At Liverpool, he regularly had midfielders providing that extra protection.

His defensive shortcomings are hardly a new discovery. Gareth Southgate regularly preferred other options with England, while Thomas Tuchel publicly questioned his defensive discipline and effort.

I haven't watched a great deal of Madrid this season, but I did watch their Champions League quarter-final against Bayern Munich in April. For me, that match summed Trent up perfectly.

Luis Díaz ran in behind him to score Bayern's opening goal, with Trent appearing to be caught asleep defensively. Yet later in the same game, he produced an excellent ball for Kylian Mbappé to score.

A defensive lapse followed by a moment of attacking quality that very few full-backs could produce. At Liverpool, the balance generally worked in Trent's favour. I don't believe Mourinho will be as willing to accept it.

The decision to leave Liverpool

There's another side to this story, and it's the one that still bothers me most.

I never liked the way Trent left Liverpool. Not simply because he joined Real Madrid, but because he was a local lad, the vice-captain and someone who was almost universally expected to become the next Liverpool captain. He allowed his contract to run down, knowing that he could leave at the end of it.

I've heard the argument countless times that he'd given Liverpool 20 years and deserved a new challenge. That argument annoys me because it makes playing for Liverpool sound like some kind of chore.

He was living my dream, and the dream of countless other Liverpool supporters, while being extremely well paid for it. He'd won every major trophy available to him at the club, Liverpool were still competing at the highest level, and there was every reason to believe more success would follow.

I understand why people say, "But it's Real Madrid." They're one of the biggest clubs in football, and had Trent gone there and become an enormous success, plenty of people would have considered it the right decision.

But I'm a Liverpool supporter. If I had the opportunity to spend my career playing for the club I've supported all my life, eventually becoming captain, there isn't another club I'd rather represent.

And even putting that feeling aside, I don't like how the contract situation was handled.

Madrid have previous when it comes to signing high-profile players whose contracts are expiring. David Alaba, Antonio Rüdiger and Kylian Mbappé all joined without conventional transfer fees. Ibrahima Konaté followed the same route from Liverpool.

Trent's situation was slightly different because Madrid eventually paid Liverpool a fee to release him a month before his contract expired, allowing him to play in the Club World Cup.

But I don't believe Madrid's repeated success in securing these players is a coincidence. In my view, they're clearly making their interest known to players approaching the ends of their contracts. It's become a familiar pattern in their recruitment, and I think plenty of Liverpool supporters had a good idea where Trent was heading long before his departure was announced.

That doesn't sit right with me, particularly when it's a local player who had the opportunity to captain Liverpool.

Big Ronald offers something completely different

While Trent struggles to establish himself in Madrid, Liverpool have found an unlikely solution at right-back in Ronald Araújo.

Araújo wasn't brought in as Trent's replacement. He arrived on loan from Barcelona primarily to provide cover at centre-back, with the ability to play on the right if needed. But with Conor Bradley injured and Jeremie Frimpong struggling to make the position his own, Araújo has been given an opportunity and taken it.

He's almost the complete opposite of Trent.

Going forward, he's nowhere near Trent's level. He doesn't possess that range of passing or the creativity that made Trent so important to Klopp's Liverpool. But defensively, I think he's in a completely different stratosphere.

He's as good a tackler as anybody in the Liverpool team, and I love the aggression he brings. He doesn't just win tackles; he sets the tone for everybody around him.

His performance against Brighton on Sunday was another example. There was a 50-50 challenge out towards the left wing where he went in and took man and ball. A proper old-school tackle, the kind of challenge you don't see nearly enough of these days.

Then there was the moment when he found himself on the floor and still managed to tackle the ball with his head. That tells you everything about his commitment.

It's not an isolated performance, either. We've seen that aggression from him several times already this season. He's become a genuine cult hero at Liverpool, despite only being at the club on loan. He fights for the shirt, and supporters recognise that.

I wouldn't take Trent back, regardless of how things work out for him at Madrid. I didn't like the way he left Liverpool, and I certainly wouldn't take him back now that we've got Big Ronald performing the way he is.

When Trent left Liverpool, I predicted he'd last around two years at Real Madrid before returning to the Premier League. I thought Chelsea might be his destination.

I haven't changed that prediction. I still expect him to leave in summer 2027, although it could be for another Premier League club. Unless Madrid change their manager, I struggle to see a way back for him under Mourinho.

I don't see Madrid wanting to keep paying substantial wages for a player who is effectively their third-choice right-back. Trent undoubtedly has the ability to contribute at the highest level.

He left Liverpool looking for a new challenge. He's certainly found one.

The grass isn't always greener.