Alex Ferguson and his assistant Archie Knox arrived from Aberdeen on the day of Atkinson's dismissal, and guided the club to an 11th-place finish in the league. Despite a second-place finish in 1987–88, the club was back in 11th place the following season. Reportedly on the verge of being dismissed, victory over Crystal Palace in the1990 FA Cup Final replay (after a 3–3 draw) saved Ferguson's career. The following season, Manchester United claimed its first Cup Winners' Cup title and competed in the 1991 UEFA Super Cup, beating European Cup holdersRed Star Belgrade 1–0 in the final at Old Trafford. A second consecutive League Cup final appearance followed in 1992, in which the team beat Nottingham Forest 1–0 at Wembley. In 1993, the club won its first league title since 1967, and a year later, for the first time since 1957, it won a second consecutive title – alongside the FA Cup – to complete the first "Double" in the club's history.
Manchester United's 1998–99 season was the most successful in English club football history as they became the first team to win the Premier League, FA Cup and UEFA Champions League – "The Treble" – in the same season.Losing 1–0 going into injury time in the 1999 UEFA Champions League Final, Teddy Sheringham and Ole Gunnar Solskjær scored late goals to claim a dramatic victory over Bayern Munich, in what is considered one of the greatest comebacks of all time. The club also won the Intercontinental Cup after beating Palmeiras 1–0 in Tokyo. Ferguson was subsequently knighted for his services to football.
In 2000, Manchester United competed in the inaugural FIFA Club World Championship in Brazil, and won the league again in the 1999–2000 and 2000–01 seasons. The team finished as runners-up in 2001–02, before regaining the title in 2002–03. They won the2003–04 FA Cup, beating Millwall 3–0 in the final at the Millennium Stadium in Cardiff. In the 2005–06 season Manchester United failed to qualify for the knockout phase of the UEFA Champions League for the first time in over a decade, but recovered to secure a second-place league finish and victory over Wigan Athletic in the 2006 Football League Cup Final. The club regained the Premier League in the 2006–07 and 2007–08 seasons, and completed the European double by beating Chelsea 6–5 on penalties in the 2008 UEFA Champions League Final in Moscow's Luzhniki Stadium. Ryan Giggs made a record 759th appearance for the club in this game, overtaking previous record holder Bobby Charlton. In December 2008, the club won the 2008 FIFA Club World Cup and followed this with the 2008–09 Football League Cup, and its third successive Premier League title. That summer, Cristiano Ronaldo was sold to Real Madrid for a world record £80 million. In 2010, Manchester United defeated Aston Villa 2–1 at Wembley to retain the League Cup, its first successful defence of a knockout cup competition.