Lonely Planet describes Lago Agrio as an "unkempt oil town, not high on tourists' lists" and advises that any visitors should "keep their heads down". This scruffy, sometimes scary, outpost of north-east Ecuador is where Antonio Valencia was born and spent much of his youth either playing football barefoot or helping his mother sell drinks outside a sports stadium.

Carved out of Amazonian jungle when, in the early 1960s, oil was discovered and Texaco began drilling, Lago Agrio has suffered for its black gold. While an amalgam of appalling pollution and destruction of rainforest became the subject of a lawsuit involving Texaco's parent company, Chevron, local problems have been further exacerbated by a flood of refugees from the cocaine wars raging across the nearby Colombian border. "Kidnapping is a problem," says Valencia, who ensured his parents and six siblings moved to Quito, Ecuador's capital, once he exported his skills to Europe. "But I had a very happy childhood."

Considering he spent countless hours scouring the streets for empty, discarded, glass bottles which his father sold to a recycling operation, that upbringing also ranks among the harshest experienced by any Manchester United player. A subscriber to the theory that tough backgrounds breed hungry achievers, Sir Alex Ferguson has extracted considerable capital from the deprivations of his own youth in Govan, but all things are relative. Set alongside Valencia's back story, the United manager's early experiences on Clydeside suddenly look safely suburban while Rio Ferdinand's infancy amid Peckham's meanest estates appears almost cosily twee.

Lago Agrio very possibly imbued Valencia with the mental resilience that facilitated the right-winger's timely recovery from a horrific ankle injury sustained against Rangers in September. Since returning to the side in March, he has helped United secure a place in the Champions League final and to within a point of a 19th league title.

Much has changed since the day, nearly five years ago, when a quiet young man arrived at Wigan, on loan from Villarreal. Noting that this 20-year-old speaking no English was barely able to read Spanish, staff wondered how he would cope – only to be astounded to learn he had swiftly, independently, found himself a house and a car. "Antonio could have buckled," says Paul Jewell, who was Wigan's manager at the time. "But he's got rare self reliance."

If such inner resourcefulness would later enable him to handle the pressures inherent in replacing Cristiano Ronaldo at United, his steely physical constitution commands instant respect. "Saw Valencia in the gym today," Ferdinand tweeted recently. "The guy throws weights like I threw Robbie Savage around. Strongest winger in the game. Fact."

Happily, Kirk Broadfoot's accidental tackle on that fateful Champions League night eight months ago has not diminished the extraordinary acceleration that makes Valencia among the fastest in his position. A combined fracture and dislocation that left bone protruding through skin imposed inevitable psychological scars yet he recovered his nerve in record time.

"When I saw my leg it was horrible," Valencia says. "I was in a lot of pain so the first challenge after returning was a bit of a concern. That tackle came against Marseille. I went in on my left foot and it did hurt a little but then I forgot about it and got stuck in."

Such commitment has characterised Valencia since, aged 10, he played his first organised game. At 16 football's lure saw him defy his father by leaving home and taking an eight hour bus journey to Quito to join El Nacional, a club with such a strong army association that players occupied barracks and partook in regular military parades. So great was his determination that when a coach advised increased pasta consumption, Valencia, confusing the word with that meaning toothpaste, dutifully gobbled tubes of Colgate.

Reward arrived with a transfer to Villarreal. Although a then slow-burning talent restricted him to a couple of La Liga appearances before a loan switch to Recreativo Huelva in Spain's second division, Valencia trained with Argentina's playmaker, Juan Román Riquelme. "I learnt a lot from Riquelme at Villarreal," he says.

So much indeed that in 2006 he emerged as one of the brightest young stars of a World Cup destined to change his life. "I was in Germany scouting and went to Poland v Ecuador looking for interesting Poles," Jewell says. "Ecuador won and Valencia's was the first name in my notebook. I liked his reading of the game, his understanding of play."

A loan move, subsequently made permanent by Steve Bruce, ensued, with the winger delighted to discover that, while he still preferred frittatas to meat pies, Wigan was rather wonderful. "Real Madrid wanted me before I joined United but I turned them down because I was happy at Wigan," says a man who meets compatriots in Bem Brasil, a South American restaurant in Manchester's Northern Quarter and lives a quiet, Paul Scholes-esque type existence with his partner, Zoila, and their small daughter. "I never felt right in Spain. I wasn't at ease but Wigan felt like home."

Bruce appreciated Valencia's twin enthusiasm for tracking back and beating his man. "Antonio's a great kid, a wonderful professional and tough as old nails," Sunderland's manager says. "He's also got something not many English players have anymore, dribbling ability."

Capable of bringing the best out of Wayne Rooney while keeping Nani on the bench, his sheer consistency, defensive discipline and high-calibre crossing revive memories of Steve Coppell hugging United's touchlines. It did not take long for fans to stop lamenting Ferguson's failure to recruit Franck Ribéry as Ronaldo's successor. Instead, at £16m Valencia represents one of his finest signings. "Antonio has a great tactical brain," United's manager says. "The boy's got everything – balance, power, speed – and he's strong as an ox."

As Ashley Cole, the England left-back humiliated when Chelsea crumbled at Old Trafford last Sunday, will testify, Valencia's catalytic role in an unexpectedly glorious Old Trafford spring cannot be over‑emphasised.