Ander Herrera has played in front of thunderous crowds at La Bombonera in the Copa Libertadores. He has shared dressing rooms with Lionel Messi and Neymar at Paris St-Germain, lifted the Europa League and the FA Cup with Manchester United, and taken on the tactical minds of Jose Mourinho, Thomas Tuchel, and Marcelo Bielsa. None of those chapters, he says, quite matches what he is doing now.

Herrera, 37, has returned to Real Zaragoza — the club where he grew up — on a free transfer, dropping from South American continental football into the Spanish third division. And he is donating his entire salary to Zaragoza's foundation.

"This is probably the last dream that I wanted to make come true," Herrera told BBC Sport. "To come back home, to the place where I grew up, that gave me the opportunity to be professional — not only in football, also as a human being. In Spain, we say closing the circle."

A club in decline

Real Zaragoza were once genuine contenders on the European stage — they famously defeated Arsenal in the 1995 Cup Winners' Cup final at the Parc des Princes. The young Herrera watched that game from home, unaware that the stadium would later become his workplace when he spent three seasons at Paris St-Germain.

That European glory feels distant now. Zaragoza were relegated from La Liga in 2012-13, two years after Herrera had departed for Athletic Club, and after 13 seasons of steady decline in the second division, the club dropped into the third tier — a notoriously difficult league to escape. Their next home fixture is against a regional side, Gimnastic de Tarragona, before roughly 6,500 fans.

"It has been so sad for all us Zaragozistas," Herrera said. "Real Zaragoza belong to Europe, they belong to compete for trophies, to be fighting with the biggest clubs in Spain and in Europe."

Giving back — literally

After 15 years away — including two spells at Athletic Club, stints at Manchester United and Paris St-Germain, and a recent chapter with Boca Juniors — Herrera felt no hesitation about waiving a salary when he rejoined the club this summer.

"I don't need a contract. I have a very successful career. I have taken care of my money," he said. "I can give this present to myself. To put that shirt on for free because I wanted to help my club, my team, my city. It's something that makes me feel so proud."

Football runs deep in Herrera's family. His father, Pedro, played for Zaragoza before becoming the club's general manager, and it was during that period that Herrera's earliest football memories were forged — including that 1995 European triumph.

Eyes on the future

Herrera is already thinking beyond his playing days. He is drawn to working with younger players and has noted the pressure that social media places on academy talents eager to accelerate their careers.

"Social media is making you run too much," he said. "Every player has his moment. Just because someone is doing it faster than you doesn't mean he is going to be a better player than you."

Should Herrera pursue coaching, he has no shortage of inspiration from the Basque Country — a region that has produced four current Premier League managers: Xabi Alonso at Chelsea, Mikel Arteta at Arsenal, Unai Emery at Aston Villa, and Andoni Iraola at Liverpool.

"I think it goes in the DNA," said Herrera, who was born in Bilbao. "The capacity to work, the capacity to respect the sport. It is difficult to explain this level of Basque coaches, but I think it is the respect for football that you can see in the Basque Country."

For now, though, coaching ambitions are secondary. Herrera has one focus — helping Real Zaragoza find their way back to where he believes they belong.

"Hopefully I can end up successful at home," he said.