Manchester United manager Alex Ferguson, the most successful manager in British football history, announced Wednesday that he will retire at the end of the season, ending a trophy-filled career of more than 26 years at the club.

He became well-known to Koreans after he signed Park Ji-sung as a midfielder in 2005, making him the first-ever Korean footballer in the English Premier League. Park played for seven years under Ferguson, who sold him in 2012 to fellow Premier League team Queens Park Rangers.

After retirement, Ferguson will remain at United as a director and club ambassador. The 71-year-old is thought to have decided to retire due to health problems, though his retirement statement did not mention health issues. He has previously said only health problems would force him to quit the job.

Ferguson has left a huge legacy at United, resuscitating a club which was next-to-last in England’s top division when he arrived at Old Trafford on Nov. 6, 1986.

He clinched his first trophy in 1990, the FA Cup, and in 1993 the team took its first English league title since 1967. He has since turned United into a European power and the world’s second richest sports club, now estimated to be worth $3.17 billion.

For 26 seasons at United, Ferguson has guided the club to a total of 38 trophies, including 13 league championships, two European Champions League crowns and five FA Cups.

Arguably the highlight of his career was the club’s unprecedented triple success in the Premier League, FA Cup and the Champions League in 1999. Following this triple triumph, he was knighted by Queen Elizabeth II.

Cristiano Ronaldo led tributes to Ferguson. The former United winger posted a picture of his first day at Old Trafford with Ferguson in 2003 on Twitter with a simple message, “Thanks for everything, Boss.”

Former United striker Michael Owen said Ferguson’s record “will surely never be eclipsed.”

According to news reports and British bookmakers, longtime Everton manager David Moyes is seen as the most likely candidate to succeed Ferguson, who previously included the fellow Scot on a short list of potential replacements.

Now United will have to plan for a future without him, but analysts expect continuing success for the club as Ferguson has sowed the seeds of a strong future.

By Chun Sung-woo (swchun@heraldcorp.com)