It has been a very busy summer transfer window for Atletico Madrid.
Los Rojiblancos finished as runners-up to Barcelona in La Liga last season, whilst they also fell short against Juventus in the last 16 of the Champions League.
Now they are aiming to push on, and have made that abundantly clear with their transfer activity. Highly-rated teenager Joao Felix has joined from Benfica for an eye-watering €126m fee, following Marcos Llorente, Felipe, Hector Herrera, Renan Lodi, Ivan Saponjic and Kieran Trippier to the Wanda Metropolitano.
Their latest acquisition is a centre back - Mario Hermoso - who has joined on a five-year deal from Espanyol.
He's fairly big news in Spain, and is rated as a fine defensive prospect. But to the worldwide audience, he's not so well known - so 90min is here to fill in the blanks for you with some things to know...
He Started His Career at Real Madrid
Atletico have already signed Marcos Llorente from their city rivals during this transfer window, and it turns out that Hermoso has connections with Los Blancos as well.
The 24-year-old started his career as a youth team player for Real Madrid back in 2005, before going on to feature for Real Madrid B and C between 2014 and 2017.
He never played for the first team, though, being shipped out on loan to Real Valladolid before moving away from the capital on a permanent basis two years ago. Now he is ready to return to play for Atletico instead - following in the footsteps of Llorente and Alvaro Morata, another Real Madrid alumni.
He Had the Chance to Re-Unite With Zinedine Zidane.....But Opted for Diego Simeone
When Hermoso was looking to make an impression at youth level for Real Madrid, there was a young manager also trying to make his way in the game. His name: Zinedine Zidane.
Of course, Zidane is once again first-team manager at Real Madrid after taking a short hiatus. Prior to leaving, he won a supreme three consecutive Champions League titles - but failed to give Hermoso a chance to shine in the first team, despite working with him at the aforementioned youth levels.
Whilst Zidane has swiftly progressed as a coach, Hermoso has too as a player. There was even talk of a reunion at Real - but he has instead opted to unite with the defensively savvy Diego Simeone. The Argentine's side is known for their defensive strength - and the young Spaniard clearly sees the potential in signing with him.
He Made His Breakthrough at Left-Back
Not all players get a smooth ride at the start of their playing careers, and Hermoso was no different - playing out of position throughout his first season of first team football.
After not making the grade at Real Madrid, the young defender wentt out on loan to Valladolid - a second division Spanish club at the time. Rather than settling in to his professional career in his preferred position, though, Hermoso played almost exclusively as a left back.
Valladolid would only finish 16th that season, but Hermoso had shown his ability to adapt, which held him in good stead when he made the step up to La Liga
His First Game in La Liga Ended in a 5-0 Loss to Barcelona
Allowed to leave by Real Madrid and then played out of position at Valladolid, Hermoso would have been grateful to get a fresh start at Espanyol. The only problem: his first La Liga start was away to Barcelona. And it did not end well.
Lionel Messi scored a hat-trick in a 5-0 thrashing as Espanyol were outclassed by their local rivals. Hermoso has come a long way since then - and will probably prefer to remember anything other than his top flight debut.
He Could Be Gerard Pique's Long-Term Successor for Spain
Some players gradually work their way through the age groups before moving in to their senior national sides. That was not the case with Hermoso.
The 24-year-old only played five times for Spain Under-19s, failing to feature for the Under-20s or Under-21s. However, his lack of experience at youth team level did not concern the national team coaches.
After impressing for Espanyol, Hermoso was brought in to the national team setup in 2018, and has started three of the side's last five games.