Los Angeles Galaxy star forward Landon Donovan announced Thursday that he will retire from professional soccer at the end of the Major League Soccer season.

Donovan and the Galaxy made the official announcement at an afternoon news conference at the team's StubHub Center stadium.

"After careful deliberation and many conversations with those closest to me, I have decided that this will be my last year as a professional soccer player,” Donovan wrote in a letter to Galaxy fans. “It has been more than anything I could have dreamed of to represent the LA Galaxy, the San Jose Earthquakes, Everton, U.S. Soccer and Major League Soccer throughout my career."

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The move will be a shock to the American soccer public and comes just more than two months after his controversial omission from the United States' World Cup squad by head coach Jurgen Klinsmann.

However, rumors surrounding Donovan's future have long swirled in soccer circles, with European agents alerted as far back as February that the U.S. national team's all-time leading scorer may not be in L.A. much longer.

Donovan was deeply hurt to be left out of Klinsmann's 23-man roster, missing out on his chance to participate in a fourth World Cup after two successful tournaments in 2002 and 2010 and a deeply disappointing one in 2006. He responded by scoring twice for the Galaxy in a 4-1 rout of the Philadelphia Union a few days later – his first goal making him the all-time leading scorer in MLS – but the burning hunger and drive that spurred him throughout his entire career still seemed missing.

That was the primary motivation in Klinsmann's reluctance to take Donovan to Brazil. The coach remained unsure as to how committed Donovan was, not only to the national team but also to the sport in general. Perceived evidence of that came with Donovan's extended sabbatical at the beginning of last year when he missed the start of the MLS season and got away from soccer.

Donovan, whose travels included a trip to Cambodia, returned to the Galaxy with their MLS campaign well underway. Even though he reclaimed his national team spot during World Cup qualifying, Klinsmann never truly trusted him again.

It has been a turbulent few years for Donovan, personally and professionally. He scored perhaps the most famous goal in U.S. soccer history against Algeria at the 2010 World Cup, was divorced from actress Bianca Kajlich in 2011 and put his prior troubles with David Beckham aside to win two MLS Cups with the Galaxy in 2011 and 2012.

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Donovan's career can only be described as a success, given his service for club and country. He will go down in most people's eyes as the best player the U.S. has ever produced. However, many in the American soccer community still would have liked to see him shine brighter in a big European league.

After struggling in Germany early in his career and again on loan to Bayern Munich (when Klinsmann was head coach) in 2009, he was twice loaned to Everton in the English Premier League but only for short, though impressive, stints.

Thursday's announcement makes the extent of his celebration Wednesday night in his record 14th MLS All-Star Game – when he scored the winning goal in a 2-1 victory over Bayern – make all the more sense.

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