'Pitbull' Gallagher leading new-look Atletico into Madrid derby

Conor Gallagher (left) has scored two goals in his past three La Liga appearances for Atletico Madrid

During nearly 13 years in charge of Atletico Madrid, Diego Simeone has led the club to unprecedented success, including two La Liga titles and Champions League qualification every single year.

But last season's disappointing fourth-placed finish, 19 points behind champions Real Madrid, was accompanied by the first major murmurings of discontent against the charismatic Argentine coach, who reacted by overseeing a major squad rebuild during the summer.

With a quartet of expensive summer signings totalling nearly 200 million euros at his disposal, Simeone is attempting to rediscover defensive solidity while also instilling a more fluid attacking style.

After undistinguished performances in the opening weeks of the campaign, that project has not convinced.

And on Sunday comes the biggest test yet for Simeone's new-look team - a home meeting with bitter local rivals Real (20:00 BST).

If Atletico can become the first team in more than a year to beat Carlo Ancelotti's men (since the Rojiblancos themselves achieved that feat last September), it could kickstart a new era.

And an England player will take a leading role.

Gallagher quickly earning admirers

One big-money summer signing who has been an unqualified success so far is midfielder Conor Gallagher.

The former Chelsea captain was initially eased into action by Simeone, but soon started to earn rave reviews.

Gallagher first really shone during a 3-0 victory over Valencia two weeks ago, capping a fine all-round display with a well-taken opening goal.

That performance prompted pundit Julio Maldonado to enthuse: "I was already convinced he's a great signing, and today he demonstrated why.

"If Simeone could design a footballer for the centre of the field, he would design a player like Gallagher. He recovers possession, works hard, he's physically tremendous and has a lot of intuition to support the attack."

He followed up with another excellent goal, securing a 1-1 draw at Rayo Vallecano, and his new manager is clearly a big fan.

"I like him a lot," said Simeone. "Gallagher has something that you can't buy: enthusiasm, passion, rhythm... wherever you put him, he has a work-rate, talent and aggression that will do us a lot of good."

Gallagher's 42 million euros price tag comes with lofty expectations, but so far he is matching them and more - even earning a new nickname for his committed style: 'Pitbull'.

On Sunday, he will relish the chance to snap at the heels of international team-mate Jude Bellingham.

New strikers settling slowly

Atletico's new strikers, however, are taking longer to settle.

The capture of Julian Alvarez from Manchester City for 75 million euros certainty raised eyebrows, with Atletico fans optimistic that the Argentine World Cup winner will emulate great number nines of the past such as Fernando Torres, Sergio Aguero and Radamel Falcao.

But so far Alvarez has struggled, often looking lost and isolated, unsure of his role.

There is a big difference between Simeone's style of play and the approach that Alvarez became used to under Pep Guardiola at City, so perhaps it's not surprising that he's taking a while to look comfortable.

Alvaro Benito of sports newspaper AS summed up the initial misgivings over Alvarez's performances, saying: "He's a long way from his best version. I don't know the reason, whether it's adaptation or if he didn't arrive in physical shape. But everyone can see it - he's far from what he could offer."

Alvarez was even dropped for Thursday's trip to Celta Vigo in favour of Simeone's son, Giuliano. But he responded to the critics by coming off the bench and meeting a delicious 90th-minute cross from Antoine Griezmann to convert the only goal of the game, which could act as the catalyst his Atletico career needed.

Alvarez's new strike partner, Alexander Sorloth, has also struggled to show his best since arriving for 32 million euros from Villarreal.

The Norwegian international is an old-fashioned target man, outstanding in the air, who bustled his way to 35 league goals over the past two seasons. But he's only managed one for his new club as the focal point of a forward line that just hasn't been clicking.

With Griezmann still pulling the strings, and wide ammunition provided by Samuel Lino and Marcos Llorente, Atletico should have all the pieces to become a formidable attacking force. But so far the new 100 million duo haven't offered any improvement on much-maligned previous pair Alvaro Morata and Joao Felix.

The pressure is starting to grow on Simeone to find a formula that allows his expensive stars to shine, and he will be desperately hoping that Alvarez's last-gasp winner on Thursday will prove to be a turning point.

Le Normand the new defensive rock?

Arguably an even more important task for Simeone is to recover the defensive solidity that marked the first decade of his reign.

Goalkeeper Jan Oblak didn't allow more than 29 league goals during any of his first seven years with the club (2014-2021), but those stingy standards have not been maintained with an average of 39.7 conceded in the past three seasons, including 43 last term.

The summer saw a defensive exodus, with Mario Hermoso, Stefan Savic, Gabriel Paulista and Caglar Soyuncu all leaving after making a combined 102 appearances last season.

In their place, Spain's Euros-winning centre back Robin Le Normand was snapped up for 35 million euros from Real Sociedad to become Atletico's most expensive ever defender.

Former Barcelona and Tottenham defender Clement Lenglet has also joined, along with goalkeeper Juan Musso to provide Oblak with some competition.

So far, so good. A great performance from Oblak helped secure Thursday's 1-0 win at Celta, meaning the team boasts the best defensive record in La Liga with just three goals conceded, and five clean sheets in the past six league outings.

The physically imposing Le Normand has played his part, and fearless but physically fragile Jose Maria Gimenez so far staying fit has also helped. If they can remain together as Simeone's central defensive pairing, Atletico will be tough to score against.

But some things never change, and the number one demand for any Atletico player remains very simple: hard work.

Koke, long-serving club captain and his manager's on-field general, reacted to the 1-1 draw at Rayo by issuing a direct warning to his team-mates as he said: "Simeone has told us that we have to run. Anyone who doesn't run won't play."

No surprise, then, that 'Pitbull' Gallagher is already such an important player, and Simeone is ready to unleash him on Sunday.