It was in London that he decided to purchase one particular model, one which cost $15,000.

For a former Premier League footballer, a hero in his native Cameroon, and one of the most successful African footballers of all time, the prospect of buying a watch was hardly the most daring of ordeals.

So after taking a glance at the watch and getting out his credit card, he says he asked the sales assistant for some help.

"I asked the saleswoman -- who was also black like me -- 'Could you show me that watch please?'

"First, I saw her turn and look at her coworkers like, 'Uh, what should I do?'

"Eventually, she let me see the watch. I looked at it and said, 'OK, I'll buy it.'

"I took out my credit card and when she went to go run it through the machine, she came back and said that it was declined.

"I asked her, 'Was it declined or did you not want it to be accepted?' because this has happened to me many times and she told me, 'No, it was declined.'"

Eto'o, who played in London with Chelsea last season, called his brother who was nearby and it was he who brought a new credit card so the transaction could be completed.

While Eto'o does speak English, his brother has a far wider vocabulary and was able to ask just what had occurred moments earlier.

"My brother can afford this and the way you're treating him shows that you think just because he's black, he can't afford this watch," said the sibling.

Eto'o then takes up the story, saying the lady in the store said she was wary of him because "we had some Nigerians in the store the other day who came with fake credit cards."

"If one of my own makes a mistake, they judge us all. Tomorrow, if a white man in Africa makes a mistake, we should judge all white people? No!

"The security guard from Senegal kept trying to justify what the lady said and I asked him where he's from. When he told me, I said, 'Ahh. If I gave you my name, you will recognize who I am?'

"He shrugged and I said, 'I'm Eto'o.' He went, 'Nooooo! Just yesterday, my wife and I were talking about you! Can I take a picture with you and send it to my wife?'

"I said, 'Yes, we can take a picture, but you made a mistake because you can't judge people by the color of their skin,' so he told me it wasn't because of our color.

"I told the lady, 'In my next interview, I'm going to tell them about this and I'll name the store so everyone can know that you treat people differently here,' added Eto'o referring to the saleswoman.

"She then realized that I could have reported what she had just done, but it was a mistake. It was a mistake of her to categorize.

"I don't think she's a racist person, but she stereotyped all black people as 'those people'."

"You're born with love, you learn hatred, that was something I learnt that day" - Eto'o on Zaragoza incident #CNNFC pic.twitter.com/DIORngYrMO — CNN Football Club (@CNNFC) March 9, 2015

Eto'o tells this story to demonstrate his belief that racism is not just football's problem but one that society as a whole must combat.

The Cameroon international has played across the world in England, Italy, Spain as well as a spell in Russia with Anzhi Makhachkala.

He says he has experienced racism on and off the field, most famously during his time playing for Barcelona.

In 2006, during a game against Real Zaragoza, Eto'o was subjected to "monkey chants" -- and the forward came close to walking off the pitch.

He says it was only because of persuasion by his teammate Fran that he stayed on and helped his side to a 2-0 victory.

In 2010, while playing for Inter Milan at Cagliari, Eto'o was again subjected to racist chanting which caused a three-minute stoppage to the contest.

The referee addressed both captains while a message was also broadcast inside the stadium warning supporters the game would be abandoned if the chanting did not stop.

Eto'o went on to score the only goal of the game as Inter triumphed 1-0.

"You have to understand that football is just a reflection of what we have in society," said Eto'o.

"It's not that football is here and society is here -- no, it's a reflection of what goes on in society.

"Football is a great opportunity for certain people, who sometimes think they're better than you or different than others, to express their views as right ... or as a chance to hurt other people.

"The first time I experienced racism wasn't on a football pitch, but the truth is that I never thought that that could happen to me on a football pitch because football is a passion, it's a feeling that touches millions of people.

"Sometimes, the fact that you're a footballer makes you think that racism can't happen to you because you bring that passion and you express a lot of things.

"When it happened to me, I couldn't believe it and in that moment, I decided to walk off the pitch."

Eto'o, now 34, believes there has been progress within the game in recent years and has decided that it is safe enough for his children to return to stadiums.

In 2007, he said he did not want his kids having to watch him being booed and subjected to racist abuse.

"I said that back then because racist incidents almost seemed to be fashionable," Eto'o explains.

"When you arrive at a football ground, this is going to happen -- when there's a black player, this will happen.

"In that moment, I said, 'No, my kids aren't going to go and see that because it will be very difficult to explain.'

"If you tell a child, go to the right and you'll get a reward, he'll always go to the right because he wants the reward. A child comes to see his father play, have fun, make people happy and what does he see?

"He sees people booing his father for being black, they make monkey noises, they throw bananas at his teammates and all that.

"But we see more and more that authorities are fighting, people are increasingly against what happens in football grounds and in society is getting better."

very proud to be receiving @TheECTR #MedalOfTolerance award tomorrow night.Should be a great evening! — Samuel Eto'o (@setoo9) March 8, 2015

Eto'o was presented with the European Medal of Tolerance from the European Council on Tolerance and Reconciliation following a ceremony in London earlier this week.

For a man who has won three European Champions League titles, his assertion that this particular award is his "biggest" gives an insight into Eto'o's mindset in dealing with the scourge of racism.

"It's the most important," Eto'o said of the award.

"It's something that affects us all and to recognize the little work that I've done, the truth is that I'm very, very happy because you can win the Champions League, you can win championships, you can score goals, but to represent a fight that affects millions and millions of people ... it's one of a kind."

Eto'o also defended Russia's record of dealing with racism, despite FIFA, the sport's world governing body, expressing its concerns over how the country's authorities deal with the problem.

I have the pleasure to announce that I have signed a contract with U.C. Sampdoria for 3.5 years. pic.twitter.com/V6Yp7U51Mb — Samuel Eto'o (@setoo9) January 27, 2015

According to a report published earlier this month by the FARE network, an anti-racism body, and the Sova Center, which conducts research on nationalism and racism, there were more than 200 cases of discriminatory behavior within the Russian game over two seasons.

The fans of CSKA Moscow, one of Russia's most famous clubs have been serial offenders in terms of racism with UEFA, the game's European governing body, handing out punishments on numerous occasions.

JUST WATCHED Eto'o: Money doesn't motivate me Replay More Videos ... MUST WATCH Eto'o: Money doesn't motivate me 03:47

Yet, Eto'o, now playing in Italy with Sampdoria, retains fond memories of Russia.

The four-time African Player of the Year joined Anzhi in 2011 following a deal which made him the highest paid player in the world on a reported salary of $13 million a year.

He scored 36 goals in 71 appearances before joining Chelsea in 2013 -- but he rejects any suggestions that Russia is a hotbed for racism ahead of the 2018 World Cup.

"At the World Cup in Russia, you'll see that there won't be incidents like this," he added.

"I hope there aren't because I've played there and I had a great time there and I know the efforts that the Russians are making to try to improve certain things that have happened there, and we have to support these efforts.

"Football is beautiful. Football is beautiful because whether you win, draw or lose, you can go and shake your opponent's hand whether they're white or black or red or blue.

"This is football. This is where football wins, but when there are incidents like this, it's shameful, but it doesn't mean this will happen in the World Cup just because it's in Russia.

"I was there and I lived a beautiful experience."