Cesar Azpilicueta was an all-encompassing leader for Chelsea - and, now retired, he reflects on how his passion for education and attention to detail helped him build a career at the highest level.
One story sums it up. Before Chelsea's Champions League final victory in 2021, Azpilicueta could not take his customary pre-match nap and opted to study instead.
He says his work towards an MBA in business management from the Berlin School of Business and Innovation took his mind off the pressure and noise on the streets of Porto.
Later that day, he lifted the Champions League trophy after captaining Chelsea to victory against Manchester City.
Azpilicueta told BBC Sport: "When I was a kid my parents pushed me to get good grades and finish school.
"I wasn't a professional footballer until I was 17, in my last year of school. Education was always important. When Covid-19 arrived, we had more time.
"I found some courses but I didn't start because I thought it was the end of my career. It was more that I wanted to learn, improve myself and do it in another language.
"It wasn't because I thought it was my last year as a footballer, but it did help me navigate the final years of my career, become a better person and a better footballer."
Azpilicueta, 37, was speaking at Arsenal's Emirates Stadium, where he joked he did not feel "entirely comfortable", while collecting a diploma in global football sport directorship through the PFA Business School, adding to qualifications that also include a diploma from Harvard Business School.
Now retired from playing after spending last season at Sevilla, he replied "maybe" when asked whether he could become a sporting director one day, but says football has left him in need of a post-career break.
Now at a "different stage of life", he cannot even contemplate playing football with friends for fun because it would trigger his competitive instincts.
"It was time to stop playing football because, even though I could probably still play, I didn't have the energy to commit myself fully for an entire season," he reflected.
"At the moment I have another commitment, which is my family. I want to play some golf and enjoy life.
"For 20 years I was constantly travelling, playing and preparing for seasons. This summer looked completely different."
After beginning at boyhood club Osasuna, Azpilicueta joined Marseille, where he learned French. However, it was his move to Chelsea in 2012 that proved transformative.
Completing his latest course highlights Azpilicueta's thirst for knowledge and a desire for constant self-improvement.
It was something he learned at Chelsea, where he arrived as a relatively low-profile £7m signing in a dressing room full of established leaders such as John Terry, Frank Lampard and Petr Cech, alongside star names including Fernando Torres, Eden Hazard and Ashley Cole.
He explained: "I started as a right winger, moved to France, then moved to Chelsea. I wasn't a star signing. I had to find my way. Left-back, wing-back, centre-back in a back three.
"It was about consistency. I had to work hard to stay fit, adapt to different managers and different positions.
"When you arrive at Chelsea, you feel the ambition straight away. Every three days you have to win. Every game and every trophy matters.
"That culture pushed me to the maximum and, especially when I left Chelsea, I felt that I had given everything I had for the club."
Azpilicueta explained how his education away from the pitch helped him develop into a leader at Stamford Bridge.
It gave him the confidence to represent Premier League players during the Covid-19 pandemic, while also helping to organise initiatives and keep the club moving forward after owner Roman Abramovich was sanctioned following Russia's invasion of Ukraine.
His defining moment came in that 2021 Champions League final victory.
There is little doubt that, having succeeded Terry and then Gary Cahill as captain, Azpilicueta ranks among Chelsea's greatest leaders. Yet he revealed that, since leaving the club in 2023, he has not returned to Stamford Bridge.
He was among dozens of players to leave after Chelsea changed ownership from Abramovich to the current American-led consortium in 2022.
"I left Chelsea, but Chelsea will always stay in my heart," he said. "I follow every game and I hope the club comes back to where it belongs.
"There are some very strong teams around and football sometimes needs a bit of time. You need connections, people playing together and understanding each other.
"At a big club like Chelsea, the demands are high. But I think that's normal. It should be demanding and ambitious because, speaking as a Chelsea fan, you always want to see the club winning trophies.
"I have confidence that manager Xabi, the staff and the players will do good work. Hopefully they can bring a lot of happiness to the fans."
He has been following Chelsea's latest captain Reece James, who he believes will grow into a better leader, since over-30 players Jordan Henderson, Danny Welbeck and Emiliano Martinez joined over the summer.
When it is suggested that he might return to Stamford Bridge in some capacity to be marked by a warm reception from supporters, Azpilicueta responds modestly: "I don't know about that.
"I will come back one day. I won't be putting on my boots, though."
