Serious injury doesn't have to mean the end of a football career, and these seven superstar players have shown over the last 20 years that even the greatest medical adversity can still be overcome to succeed at the highest level.

Nwankwo Kanu

Nwankwo Kanu of Arsenal

Nigerian legend and Premier League cult hero Nwankwo Kanu overcame a serious heart defect that was discovered at the age of 20, shortly after he captained his country to Olympic gold in Atlanta, and went on to enjoy a long, successful and varied career thereafter.

Having recently signed for Italian giant Inter, Kanu underwent open heart surgery in November 1996 to replace an aortic valve. He returned to action six months later, and although things never quite worked out in Italy, the tall forward was an instant hit after joining Arsenal.

He was named African Footballer of the Year in 1999 (both the BBC and CAF awards) and scored a famous hat-trick for the Gunners against Chelsea. Kanu later joined West Brom and also netted the winning goal in the 2008 FA Cup final during a memorable stint at Portsmouth.

Eric Abidal

Barcelona's players toss teammate Barcel

Suffering with a potentially lethal illness rather than a typical injury, Eric Abidal defied liver disease to continue his playing career at the very highest level with Barcelona. The French defender underwent surgery in March 2011 to remove a tumour, but was back on the pitch in time to play 90 minutes of that season's Champions League final against Manchester United in May.

A year later, the defender required a liver transplant - Barça team-mate Dani Alves famously offered to be the donor. Within nine months of the operation Abidal was back in training and made his comeback on the pitch before the end of the 2012/13 season.

Abidal then spent a full season at Monaco in 2013/14 as well as a further half campaign with Olympiacos in 2014/15 before retiring at the age of 35.

Petr Cech

Carling Cup Final: Chelsea v Arsenal

Petr Cech wasn't just in danger of losing his career from a now infamous collision with Reading's Stephen Hunt in 2006, he was at risk of losing his life after the sickening impact left the then Chelsea goalkeeper with a depressed skull fracture. It makes his return to the top since even more remarkable.

Even now, he is unable to recall the events and doesn't remember anything for a period of around four days after the incident. But Cech was back on the field just three months after and wasted little time in re-establishing himself as one of the very best goalkeepers in the world.

In 2015, having since joined Arsenal, he broke the Premier League's all-time clean sheet record and is widely regarded as one of English football's greatest ever foreign imports.

Ruud van Nistelrooy

Bolton v Man Utd

Ruud van Nistelrooy was set to become Manchester United's record buy in the summer of 2000 until concerns over a knee problem saw the transfer called off. Just a day later the striker ruptured cruciate ligaments in a PSV training session, leaving him sidelined for many months.

United gambled on Van Nistelrooy's fitness a year later - his career had been saved by famed surgeon Dr Richard Steadman - and completed the deal for £19.5m a year later. The risk paid off and the reigning English champions hit the jackpot.

The Dutchman scored twice on his Premier League debut and finished his first season with 36 goals in all competitions. He then netted a further 44 times during the 2002/03 campaign - still second in club history for goals scored in a single season - and had 150 to his name at United before joining Real Madrid in 2006 and winning successive La Liga titles.

Henrik Larsson

Henrik Larsson of Celtic celebrates scoring

After 54 goals in his first 107 games for Celtic, Henrik Larsson saw his career suddenly at risk after breaking his leg in two places during a UEFA Cup game in October 1999. The Swede made his comeback on the final day of the 1999/00 campaign and what was to follow was astonishing.

Larsson subsequently enjoyed the most prolific season of his career the following year, scoring 53 times in just 50 appearances and collecting the European Golden Shoe for his 35 Scottish Premier League goals.

He netted another 120 times for Celtic in three more seasons between 2001 and 2004, before proving his quality at the very highest level for Barcelona with a decisive impact in the 2006 Champions League final, as well as short but memorable stay at Manchester United.

Alan Shearer

Alan Shearer of Newcastle

But for three serious injuries several years apart, one can only speculate how many more goals Alan Shearer might have scored in a glorious career that saw him become the Premier League and Newcastle's all-time leading goalscorer anyway.

Shearer's first major problem came as he suffered knee ligament damage in December 1992, returning to score 108 times for Blackburn in the three seasons that followed, even claiming a Premier League title for the Lancashire club in 1994/95.

He later ruptured ankle ligaments in the summer of 1997, having joined Newcastle 12 months earlier, and missed more than half the 1997/98 campaign. Shearer was back among the goals when he returned to fitness but subsequently also missed a lot of 2000/01 as well, before once again scoring freely after Dr Richard Steadman had saved his career.


Brazil's forward Ronaldo celebrates after scoring

Ronaldo is another superstar who owes his career to Dr Richard Steadman after multiple serious knee injuries threatened to completely derail one of the greatest talents that world football has ever seen.

The phenomenal Brazilian encountered his first issues at PSV Eindhoven while still a teenager, but he recovered after missing much of 1995/96 to justify Barcelona making him the most expensive player in the world, scoring 47 goals in 49 appearances for the Catalan giants.

But it was during his time at Inter that true miracles happened. Ronaldo was forced to miss the best part of three years from 1999, but still made the Brazil squad for the World Cup in 2002. Unbelievably, he exploded back into life, scoring eight times at the finals as Brazil lifted the trophy, while also exorcising his own personal demons from the 1998 tournament.

Ronaldo then went on to score 85 goals in the next three seasons with Real Madrid and later became the World Cup's all-time top goalscorer in 2006 - a record broken by Miroslav Klose in 2014.

FUSSBALL: Nationalmannschaft 1998 BRASILIEN/BRA am 25.03.98