Conor Gallagher: 'Chelsea since birth' but loving life at Atletico Madrid under Diego Simeone after being deemed surplus to requirements by Enzo Maresca

Would Gallagher have ever left Stamford Bridge had Chelsea not forced him out? Probably not. He'd been at the club since the age of six. Gallagher was effectively "Chelsea since birth", as the fans pointed out in a banner unfurled ahead of a game against Tottenham last season.

He was treated terribly during his horribly protracted transfer to Atletico, with the deal in danger of complete collapse at one point when Samu Aghehowa's proposed move in the opposition direction fell through. Even then, though, Gallagher refused to speak ill of the club. Instead, he thanked Chelsea for "making my dreams come true".

"It's been an absolute honour every time I put on the shirt... and I loved every moment," he said after his exit was finally confirmed. "These memories will last forever. I appreciate all the love and support from the fans. Hearing the chant of my name at the Bridge is a special feeling, and the banner you displayed [against Spurs] meant the world to me."

Happily for Gallagher, though, he's quickly become something of a cult hero at the Metropolitano too.

Atleti fans were thrilled to see Gallagher say a few words in Spanish at his official unveiling at the Metropolitano alongside fellow star summer signings Robin Le Normand, Alexander Sorloth and Julian Alvarez, and the man referred to as a "pitbull" during his introduction to the crowd was blown away by their warmth of his reception.

"It's not really a thing in England is it, so the ceremony was a bit of a surprise to me," Gallagher told The Mirror. "But I was really excited for it, and I could tell right away how passionate the fans are just from that. So, it built up my excitement even more to start playing the games."

Gallagher went about further endearing himself to the supporters by scoring in back-to-back games in La Liga, against Valencia and Rayo Vallecano, less than a month later, while at the same time impressing all and sundry with his all-action approach.

Before moving to Madrid, Gallagher had "spent a lot of time" at Euro 2024 talking to his England colleague Kieran Trippier about the full-back's spell at Atleti, revealing: "He only had amazing things to say about the club, the manager, the players, the city, the whole thing!" It was obvious, though, that the manager in question was the determining factor in his decision.

Diego Simeone is renowned as one of the most demanding coaches in world football. Even the most talented players are not tolerated by the abrasive Argentine if they are not also willing to work hard. Luckily, a lack of effort was never going to be an issue with Gallagher.

"You can see the type of players he likes and he needs in his kind of system, and I think it fitted me perfectly," Gallagher told ESPN in December. "So, that was one of the decisions why I felt it was a perfect move for me. I now feel settled in the club too. Everyone has made me feel at home and it's been brilliant.

"Of course, it's been difficult at times and [I'm] still learning the language and getting used to new team-mates."

Gallagher has had his issues at Atleti. There have been some poor performances during his attempts to integrate into his new surroundings, most notably in the chastening 4-0 Champions League loss to Benfica, when he was one of several players to underwhelm. He's still not a certain starter in Simeone's side either - but then, not many players are.

The main reason behind the club's summer spending spree was to add greater depth to a squad that finished fourth in La Liga last season and was surprisingly eliminated at the quarter-final stage of the Champions League by Borussia Dortmund. It's a case of Mission: Accomplished in that sense, with Atleti locked in a fascinating three-way fight with city rivals Real and Barcelona for the Liga title that looks set to go right to the wire.

The Rojiblancos also progressed directly to the last 16 of the Champions League by finishing fifth in the league phase thanks in no small part to impressive wins over Paris Saint-Germain and Bayer Leverkusen and, as Alvarez pointed out, "We've been playing really well because the team as a whole is performing excellently. Everyone contributes, even those coming off the bench."

Saturday night was an excellent case in point.

Alvarez, Marcos Llorente and Gallagher all came off the bench in Saturday's clash with Athletic Club, and the first two combined to break the deadlock, with the Argentine slotting home the Spaniard's sublime through-ball.

However, it was Gallagher who provoked the most animated reaction of the evening from Simeone and his assistant coach Nelson Vivas when he won two tackles in the space of five seconds in injury time, as Atleti fought heroically to eke out a win that temporarily sent them top of the table.

It was a moment that typified the Rojiblancos' remarkable resilience and showed precisely why Gallagher is considered such a valuable member of Simeone's squad. As the coach said earlier in the season, "He arrived with a lot of enthusiasm and we needed that kind of player in midfield because he makes us better. He does not stop giving his best in every game situation in which he participates."

Tuesday at Santiago Bernabeu will be no different, whether Gallagher starts or not. The 25-year-old's energy has regularly aided Atleti's attempts to see out close games in recent weeks, but there's also a real chance he'll be selected on the left-hand side of a compact midfield four as Simeone looks to nullify Real's attacking threat.

Whatever the manager decides, though, it's clear that he considers Gallagher a player he can count on to do whatever is asked of him. Maresca may not have deemed the Cobham academy product a good fit for his footballing philosophy, but Gallagher is already feeling "right at home" in Simeone's side.

"The manager just wants everyone to work as hard as possible, to prepare for each game and then win, and I think that's perfect for me," the Surrey native said. "He is one of the best managers in the world, I already love how he is, with me and with the team, and I'm looking forward to working with him for years to come."