As supporters of Colombia prepare to descend on Fortaleza in their tens of thousands ahead of the World Cup quarter-final against Brazil on Friday, many will pack one special addition to their list of belongings: a photograph of Andrés Escobar, their former captain and a man known simply as El Caballero del Futbol: the gentleman of football. It is 20 years to the day since Escobar was shot dead after scoring the own goal that effectively sealed Colombia's elimination from USA ’94.

As the nation now prepares for its most important match, the proximity to the anniversary of perhaps the most tragic episode in World Cup history is hard to ignore. Escobar should now be 47. He had been planning marriage, having children and a move to AC Milan that would have confirmed his status as one of the world’s best defenders. He would surely also have revelled in the emergence of a wonderful new generation of Colombian football stars at this World Cup.

Instead, he was a victim of the lawless chaos that gripped Colombia at a time when football also became wrapped in the tentacles of organised crime. The relationship between the illegal narcotics industry and the rise of Colombia’s previous 'golden generation’ – the team of Escobar, Carlos Valderrama, Faustino Asprilla, René Higuita and Freddy Rincón – is explored in the acclaimed ESPN documentary The Two Escobars. It is a story of how Colombian football boomed during the late 1980s and early 1990s with the help of funding from major drugs bosses and then fell into a long period of decline in the aftermath of Escobar’s murder.

Central to that narrative is Pablo Escobar, a namesake but no relation to Andrés, who was head of the multi-billion-dollar Medellín drug cartel. Once listed as the richest criminal in the world, he was also infamous and his cartel were accused of numerous killings. Pablo’s great passion was football. He built pitches for the poor and helped fund the Medellín-based Nacional team.

At his ranch, he would fly in great footballers of the day for matches on a purpose-built pitch that would involve huge side-bets with other drug lords. Andrés Escobar was part of the Nacional team that rose to become the first Colombian side to win South America’s equivalent of the Champions League – the Copa Libertadores – in 1989.

“Two factors converged,” said Francisco Maturana, who was the coach of Nacional and later the Colombia national team. “One, we had exceptionally good players. Two, we had the money to keep our good players. The introduction of drug money in soccer allowed us to bring in great foreign players. We were living in a violent time, in a country fraught with social problems that could not be divoRodrrced from football. The drug trade is an octopus.”

Even when Pablo Escobar surrendered himself to the Colombian authorities in the early 1990s, the players visited him for lunch and a match on a pitch that had been built at the Catedral Prison.

Colombia went into the 1994 World Cup having lost just once in 26 matches. After their 5-0 drubbing of Argentina in qualifying, Pele had predicted that they would win the tournament. Leading politicians would attend Colombia matches and the football team was seen as the main hope for national unity.

The backdrop, though, was still of terrifying social and political problems. Pablo Escobar was then killed in December 1993, anarchy ensued and Colombia had the highest murder rate in the world.

Andrés Escobar would be Colombia’s captain at the 1994 World Cup. “We are all working for a common cause – to make our country proud,” he said, upon arriving in the US. “We’re trying to not focus on the violence. I find motivation in the good things to come. I try to read a bit of the Bible each day. My bookmarks are two photos. One of my late mother, the other of my fiancée.”

Family members tell of Escobar’s dedication, his desire to help Colombia and his unease with the team’s link to the drugs lords.

“He was a very serious, disciplined student but after school it was all football,” María Ester Escobar, his sister, said. “Every morning before school, Andrés went to mass with our mother. We were a devout family but our mother suffered from cancer and passed away at 52. He turned to soccer to channel his feelings.

“Andrés knew he was becoming famous but he remained humble. He felt a responsibility to improve Colombia’s image. Andrés wasn’t OK with having to visit Pablo [Escobar]. He told me, 'María I don’t want to go but I have no choice’.

“Before the World Cup, Andrés spoke about his future in Italy. He wanted me to spend all my vacations there. It was a beautiful dream.”

With Higuita, the usual goalkeeper, in prison following his visits to Pablo Escobar, Colombia lost unexpectedly 3-1 eo Romania in their first match. The brother of defender Chonta Herrera was then killed in a suspicious car accident. Escobar had to persuade his team-mates to stay at the World Cup. Before their second game, against the USA, the team received death threats on the TV in the hotel they were staying at. “Someone programmed the hotel’s TVs – it freaked us out,” Maturana, the coach, said. With various drugs lords desperate to see certain players starting for Colombia, Maturana was also told he should drop Barrabas Gómez or have the entire squad murdered. “I couldn’t put another’s life in danger – Barrabas was a key player but they had me beat,” Maturana said. “We called home, there were riots, complete chaos and that’s how we entered the field.”

Colombia still dominated against the USA until the 35th minute, when Escobar scored the one and only own goal of his career. At full stretch in an effort to cut out a John Harkes cross, he made contact with the ball and sent it rolling into an empty net.

“In that moment, my nine-year-old son turned to me and said: 'Mommy, they’re going to kill Andrés’,” Escobar’s sister, María, said. “I replied: 'No sweetheart, people are not killed for mistakes.’ Everyone in Colombia loves Andrés.”

Escobar never watched a replay of the incident. His team-mates say that he was devastated but, after returning home to Medellín, he decided that it would be best to show his face in the city. Some of his friends had reservations. “I said: 'Be very careful, the streets are very dangerous – conflicts are not resolved with fists’,” Maturana said. “But Andrés said: 'No I must show face to my people’.”

According to eye-witnesses, Escobar arrived at the El Indio Bar on July 2 with friends and was taunted by another group about the own goal. He left but was followed and further provoked. He got upset, tried to explain it was an “honest mistake” and then, as the situation escalated, was shot six times in the back. “Something was ripped out from within me,” Pamela Cascardo, Escobar’s fiancée, said. “One day you have the love of your life, plans to get married, have children. Then you wake up and it’s all gone. For me, life didn’t go on. It stopped.”

The motive behind Escobar’s killing remains shrouded in mystery. It was initially thought to be revenge for heavy betting losses on Colombia at the World Cup. Two witnesses gave the number plate of a car in which some of the perpetrators made their escape. It was linked to the Gallón brothers, drug traffickers who had left Pablo Escobar’s cartel. Jhon Jairo Velásquez Vásquez, who was an enforcer for Pablo Escobar, alleged in the 2010 Two Escobars documentary that $3 million was paid to persuade the prosecutor’s office to focus their investigation on one of the bodyguards.

Humberto Castro Muñoz confessed to Escobar’s murder and was sentenced to 43 years in prison, only to be released for good behaviour after serving just 11. The Gallóns were cleared of any wrongdoing. “Andrés’s mistake was talking back to these guys,” Velásquez said. “It had nothing to do with betting. It was a fight, that’s all.”

More than 120,000 people lined the streets of Medellín for Escobar’s funeral. César Gavaria, then the president of Colombia, spoke to the mourners. “Andrés Escobar will remain in our hearts as our hero of moral integrity, as a family man and exemplary Colombian,” he said. “Colombia must not let its best children be expelled from life’s playing field.”

Colombian football, though, was left devastated. Herrera had a nervous breakdown, Asprilla and Valderrama no longer wanted to play for the national team. This World Cup is the first time Colombia have even qualified since 1998.

“Many people who lived for soccer left the sport after what happened to Andrés,” Maturana said. “We exchanged winning for our safety. Now we’re cleaning up our streets and starting to build again.”

Beyond campaigns on social media and the photographs that fans will carry on Friday, it is still unclear how, or even if, the anniversary of Escobar’s death will be marked this week by Fifa or the Colombian Soccer Federation.

Escobar is regarded as the most popular footballer in his country’s history but, equally, Colombia wants the world to see it in a new light. Old stereotypes are frowned upon, even if a 24-hour drink ban had to be imposed on Bogota, the capital city, after 10 people died during celebrations for the country’s 3-0 win against Greece. There is now a statue of Andrés Escobar in Medellín and his brother will speak at a special event to be held this week by his former club side Nacional. His family also continue to take strength from the poignant words he penned in Bogota’s El Tiempe newspaper just a few days before his death.

“Life cannot end here,” wrote Escobar. “We have to go on. No matter how difficult, we must stand back up. We’ll see each other again soon because life does not end here.”