After returning to his beloved Fluminense and helping save them from relegation in December, 40-year-old Thiago Silva walked the length of the pitch on his knees in an act of gratitude.

On Tuesday, Silva will lead the Brazilian team into a Club World Cup semi-final against his former side Chelsea.

Fluminense have kept three clean sheets with Silva at the heart of their defence this tournament and beat Inter Milan and Al-Hilal to reach this stage.

Silva remains close to Chelsea, where he spent four years of his career, with his two sons Isago and Iago both playing in the club's academy and still living in London.

When asked what he knows about the current Chelsea side, having visited the club's Cobham training ground in both September and December, Silva, said: "I'm not a spy. I don't know [Enzo] Maresca that well, but I do know a lot of players there. I talk to them practically every week.

"I'm trying to help in the best way possible in terms of information, but we know that in practice it's completely different from everything we studied.

"We just hope to have a perfect day so that we can play the best game possible. I'm happy about this match. It's going to be a special day for me, but it will be even more special if we win."

Silva's incredible journey

Silva gained his nickname 'O Monstro' - Portuguese for monster - because of his imposing playing style but could easily have earned the moniker through his comeback story.

Growing up in the Campo Grande favelas in Rio de Janeiro and being abandoned by his father at the age of five, the pathway to becoming one of the 21st century's greatest centre-backs has not been straightforward.

A route into European football came for Silva as he left second-tier Juventude to join Porto in 2004, aged 20, beginning in the Portuguese club's B team.

However, during a reserve trip to Thailand, the defender began to feel ill with cold-like symptoms.

In the days that followed, he agreed to a loan move to Dynamo Moscow, but, after only a handful of sessions, Silva struggled to breathe or perform even basic tasks.

He was hospitalised and diagnosed with tuberculosis. Doctors informed him that if he had waited just two more weeks at home rather than seeking medical help, he could have died.

Silva was stable but not responding to treatment and was isolated in a Moscow facility for six months due to the contagious nature of the disease.

He was finally able to return to Portugal and, after a further six months, was cured.

That year out of football was a major setback, in footballing terms, and Silva returned to Brazil, joining Fluminense to rebuild his career.

His return to Europe after two and a half years saw him become one of the world's best at AC Milan and Paris Saint-Germain, ultimately seeing him earn 113 caps for Brazil.

What he achieved at Chelsea

Chelsea fans still sing about their former defender.

The impact of Silva was enormous on the English club's run to win the Champions League in 2021 which has seen the club participate in this newly expanded Club World Cup.

He also won a UEFA Super Cup and Club World Cup - in a previously shorter format - during an impressive spell with the Blues.

Former Chelsea teammate Marc Cucurella, said: "He's a legend of football, a top player. He's only played for big clubs and texted me before this game saying, 'let's go, hopefully we can see you in a couple of days'.

"We have the opportunity to play against him, and hopefully we can do good things and win this game and play in the final, which is what we want to do."

Silva says of his journey through west London: "I am grateful for everything I have been through. Chelsea were a very special team in my life. I won one of the biggest titles of my career there."

The coach on the pitch for Fluminense

Silva was seen delivering a team talk during a cooling break when Fluminense were leading Inter Milan 1-0 but under heavy pressure.

He was captured by cameras suggesting a tactical switch to a 5-4-1 formation and also recommended putting Everaldo, a striker, on the wing and Jhon Arias, a playmaker, up top.

Manager Renato Gaucho, agreed and Fluminense got one of the best results in their 123-year history as they snatched a late second on the break.

When asked about Silva, Gaucho said: "I usually say that Thiago is a monster on the pitch.

"He has helped us a lot, he knows European football and Chelsea well. He is essentially a coach on the pitch. His experience is critical - along with his high quality football.

"He talks a lot to his teammates on the pitch, especially in these major matches, against major international teams. His experience and style of play are paramount for us.

"We are ugly ducklings in financial terms but that doesn't mean we can't win the Club World Cup."

Silva, who is doing his coaching badges, said: "My exchange with him was important. I think it's normal in football for the coach to be open with his captain. Renato is very open with me. Not all coaches have the humility to understand what the player feels."