'I told Guardiola he wasn't a great player, where Eto'o goes, controversy follows'

The striker contrived to become embroiled in a bust-up with his new club, Sampdoria, just a week after arriving at the Stadio Luigi Ferraris - but just who is the real man?

A recent study by the University of York attempted to model the specific physical attributes that underpin our first impressions. The work showed how small changes in the dimensions of a face made it appear more approachable, dominant or attractive.

Results found some obvious trends; masculine faces with strong jawlines were perceived as dominant, while approachability and trustworthiness was seen in those with broad smiles.

It is a project that might have interested Samuel Eto'o, who would have discovered that a curled lip and slumped shoulders were not the best way to endear himself to his new employers.

At 33, the value of making a good first impression appears to have been lost on the striker, who, less than a week after joining Sampdoria from Everton, incurred the wrath of coach Sinisa Mihajlovic with another unwise display of dissent.

After making his debut as a substitute in the club's 5-1 defeat at the hands of Torino on February 1, the striker and the rest of his team-mates were informed that their Monday off had been cancelled and replaced with a double training session.

Having appeared at the morning practice, Eto'o then failed to show in the afternoon after storming out of the club's Gloriano Mugnaini complex, resulting in a heated bust-up with his new coach.

An apology from the former Cameroon international settled the feud, with the player starting Sunday's 1-1 home draw with Sassuolo from the bench before being introduced in the 70th minute.

The row may well have been forgiven but the damage has already been done, with the incident adding another negative footnote to a career which has delivered many sizeable servings of controversy.

For a player who has won an Olympic gold medal, three Champions League titles, the Africa Cup of Nations twice and four African Footballer of the Year awards, Eto'o remains a polarising figure who has never enjoyed the same adulation afforded to another African star of his generation, Didier Drogba.

His supporters will tell the story of the small boy nicknamed 'little Milla' - after Cameroon great Roger - with the million-watt smile who grew up the son of an accountant in the nation's capital city of Douala before leaving his homeland for Europe and becoming one of football's biggest stars.

They will also talk of the many millions from his personal fortune that he has invested in the Samuel Eto'o Private Foundation, a non-profit organisation operating in West Africa that provides emergency aid for young people and encourages education, basic health and social inclusion for the disadvantaged.

Pep Guardiola, however, might prefer to paint a picture of a smiling assassin. The former Barcelona boss won his first Champions League as a coach in 2009, with Eto'o scoring the opener in the 2-0 win over Manchester United in the final.

But their relationship was a fractious one and the forward was eventually pushed out of the club at the end of Pep's first season. Eto'o revealed details in March last year of one early exchange between the pair.

"I first of all reminded Guardiola that he'd never been a great player," he said in an interview with beIN Sports. "As a coach he had proven nothing; he didn't even know the story of the dressing room."

His relationship with Jose Mourinho is equally intriguing. Before leaving Barcelona for Inter in 2009, the Cameroonian gave an interview during which he claimed that he would never play under the Portuguese, only to then join him at San Siro a matter of months later.

They had first became acquainted in the tunnel at Stamford Bridge following Barca's 4-2 second-leg defeat to the Blues in the last 16 of the Champions League in 2005.

"I know you are a great person and a great coach," the then-Barcelona striker told the Chelsea manager in despair at their 5-4 aggregate defeat, "but in truth you are just a s***!"

Somewhere, though, a respect blossomed between two emotional characters. At Inter, one of their egos had to give, with Mourinho successfully suppressing Eto'o's sense of entitlement to the point at which he willingly played out of position for much of the season, as he operated as a winger and even an emergency wing-back on the way to winning the 2010 Champions League.

It is understandable, then, given the striker's self-sacrifice and loyalty towards Mourinho's values that he was more than a little hurt when his mentor suggested that he was "32 or 37" in a conversation secretly filmed by Canal+ during his solitary season with Chelsea last term. Eto'o responded by mocking Mourinho as he celebrated his next goal - feeling his back as he hunched like an old man by the corner flag.

At international level he retired from duty once and for all in August after being dropped from Volker Finke's squad for their Africa Cup of Nations qualifiers in September and stripped of the captaincy. Cynics will point to previous faux-retirements, notably back in 2013 when the nation's president Paul Biya personally persuaded him to change his mind, while he was also banned for eight months for leading a player strike in 2011. Eto'o led a similar stand of defiance prior to last summer's World Cup but escaped punishment.

Mercenary or maverick? Roberto Carlos first befriended the African at Real Madrid in the 1990s before they met again at Anzhi Makhachkala and it is he who comes closest to solving the Eto'o code.

"I've known Eto'o since he was 16, and from that time on he's always been a good guy who I've liked a lot," Roberto Carlos told Globo.

"He's a good person but there is a part of him that thinks 'I, and not the group', which is really damaging.

"A moment arrived when Eto'o thought to interfere with my work, to control the club, taking my position and that of Guus Hiddink. He did everything at Anzhi, except play football."

The Brazilian sums his former teammate up nicely. A nice person but with an attitude which holds him back and makes life difficult for him and those surrounding him.

However long it lasts, his time at Sampdoria certainly will not be dull.