Busst played as a defender, and started his career at non-league side Moor Green in Birmingham, before moving to FA Premier League side Coventry City in August 1992. He made his professional debut in an FA Cup match against Norwich City on 13 January 1993, and his Premier League debut three days later against the same side. Busst made ten league appearances in his first professional season, and went on to make 50 league appearances in total for the club, scoring 4 goals.

His professional playing career came to an end on 8 April 1996, whilst playing for Coventry against Manchester United. Two minutes into the match, having ventured forward after his team won a corner, Busst collided with United players Denis Irwin and Brian McClair, resulting in extensive compound fractures to both the tibia and fibula of his right leg. The match had to be delayed for nine minutes, due to Busst needing to be removed from the field on a stretcher, and blood was cleaned off the grass with water and sand. Manchester United’s goalkeeper Peter Schmeichel vomited on the pitch upon seeing the injury. It was rumoured that Schmeichel had counselling for the effect of seeing the injury, but he said that this was not so. The injury is often cited as one of the worst in the history of football. The subsequent injuries suffered by Eduardo da Silva, Luc Nilis and Preston Burpo have been compared to Busst’s injury by many observers, though Busst’s is generally considered as by far the worst.

Busst’s injuries were so bad that at one point he ran the risk of having his leg amputated. While in hospital, Busst contracted MRSA, which caused further damage to the tissue and muscle in the injured part of his leg. Despite having 22 operations, Busst remained a member of the official Coventry squad for a further seven months, but never played professionally again, and he retired from the game on 6 November 1996 on medical advice, as his doctors had warned him that he would never regain full fitness to play professional football. It was not the break itself that ended his career, but the following infections. Just weeks before his retirement, Busst had been hoping to return to training the following spring and be ready for first team action by the start of the 1997–98 season.

His testimonial match, played on 16 May 1997 against Manchester United, was a sell-out. England internationals Paul Gascoigne and Les Ferdinand and best friend Jonny Hansen guested for Coventry in the game, which was also notable for being the last game that United captain Eric Cantona played before he announced his retirement as a player two days later.

Busst also trained as a coach, earning UEFA coaching badges. Busst went on to manage the non-league sides Solihull Borough (from 2000 until 2003) and Evesham United (from 2003 to 2006.) He briefly acted as defensive cover in 2008 for Midland Combination Premier Division side Highgate United, where his brother Paul was the club’s assistant manager.