We take a look at promising youngsters who never really fullfilled their expectations.
Freddy Adu (24)
Freddy Adu is a name every football fanatic should recognises.
Adu started his professional career at D.C. United, and was considered one of the world's most promising youngsters, making his debut for the club at the age of 14.
Adu played for D.C. United for two years, scoring 12 goals in 87 appearances in the MLS.
He was then signed by Real Salt Lake in the MLS, scoring one goal in 11 appearances.
Adu was called up for the United States national team at age 16, being the youngest player ever to play for his home country.
In 2007, Adu was signed by Benfica in the Portuguese Primeira Liga. His spell at Benfica has to be considered a major disappointment, making just 11 league appearances, scoring 2 goals.
Spells on loan to several clubs around Europe followed, including AS Monaco, where he played nine league games without scoring a single goal for the club.
In August 2011, Adu returned to the United States to sign for the Philadelphia Union. In April 2013 he was sent on loan to Brazil to play for Bahia in the Brazilian Premier League. He has currently yet to make a major contribution for the club, only making two appearances so far.
Kerlon Moura Souza, better known as Kerlon, was once considered an outstanding talent, being named the top scorer of the 2005 South American Under 17 Football Championship as well as receiving "The Best Player Award" in the competition.
Kerlon started his professional career at Cruzeiro, and was quickly spotted by the top teams around Europe, signing for Inter Milan in 2008. He made no league appearances for the club, and simply never recovered after his spell at the San Siro. He was sent on loan to four clubs around Europe, never making his mark for any of them. Today Kerlon is playing for Fujieda MYFC in the Japanese Football League, which is the 3rd highest division in Japan.
Michael Johnson (25)
Michael Johnson, what can we say about him? Well, the man who started his professional career at Manchester City, has had one of the most depressing careers in football history.
Johnson made his professional debut for Manchester City in 2006, earning plaudits for his performance against Wigan Athletic. Although his second game for City came only in March 2007, Johnson was considered to be incredibly talented, and after starting for City in 2007 against Middlesbrough, he made several first team appearances, receiving positive reactions from the media.
In October 2008, Johnson suffered heavy injury, keeping him away from football for nearly a year. After his injury, Johnson never fully recovered, only making 27 appearances for City in over 3 years.
During the 2011-2012 season, Johnson was sent on loan to Leicester, signed by his former boss Sven-Göran Eriksson.
However, his loan spell ended prematurely in January, when he sustained an injury, only making nine appearances for the club. Johnson was praised by his former teammate Dietmar Hamann who described him as an "outstanding talent", comparing the midfielder to Michael Ballack.
Representing England's under-19 and under-21 teams, Johnson was described as one of England's most promising youngsters. Today Johnson is currently a free-agent, and as sad as it sounds his career has most likely ended.
Francis Jeffers (32)
It has to be said that Francis Jeffers never got close to what was expected of him. Jeffers has played for 11 clubs in his career, never showing what was expected of him after he left Everton in 2001. Jeffers scored 18 goals in 49 matches for Everton in the Premier League.
In 2001, Arsenal showed an interest which ended with Jeffers signing for the club and Arsenal paying £8million for the striker, which made made him one of Arsenal's most expensive purchases yet.
The Englishman played 22 league matches for Arsenal, scoring four goals, and he was quickly loaned back to Everton, where he represented them in 18 matches, not scoring a single goal.
After playing for nine different clubs after leaving Arsenal, Jeffers is currently playing for Accrington Stanley in League 2.
Giovani Dos Santos (24)
Although this might be controversial, Dos Santos is a real disappointment in my opinion. After being brought up by the Barcelona youth system, Dos Santos was bought by Tottenham in 2008, after making 28 league appearances for the Catalan club.
Frank Rijkaard, who managed Barcelona at the time, had already described Dos Santos as an amazing player, who he would love to keep at the club. After joining Tottenham for €6m, Dos Santos simply failed to impress for Spurs, later being sent on loan to Ipswich Town, where he scored four goals in eight appearances.
The Mexican was given few chances in the first team after returning from Ipswich, later being sent on loan to Galatasaray and Racing Santander, where his performances were mediocre at best.
Despite his young age, Dos Santos has been capped 68 times for Mexico, scoring 14 goals. In July 2013 Dos Santos signed for newly-promoted La Liga side Villareal, which could be a brand new start for the striker.
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