Ferguson spent most of his playing career at Rangers, in two spells either side of a £7.5 million transfer to English club Blackburn Rovers. He totalled 431 games and 60 goals for Rangers, whom he captained between 2000 and 2003 and again between 2005 and 2009. Ferguson won the Scottish Premier League, Scottish Cup and Scottish League Cup five times apiece for Rangers, including a treble in 2003, which earned him the honour of SFWA Footballer of the Year. He also helped Rangers to reach the 2008 UEFA Cup Final.