Gritt spent most of his playing career with Charlton Athletic, after joining from home town club Bournemouth in 1977. In his first spell with Charlton, he experienced one relegation to the Third Division, one promotion to the Second Division and one promotion to the First Division. In 1989, he moved to Walsall for a brief spell but soon returned to Charlton. In his second spell, he experienced another relegation in 1990. In all, Gritt made 435 appearances for Charlton, with 26 goals, placing him fifth on Charlton's all-time appearance list. He played a further two seasons after being appointed manager, retiring in 1993. He later had brief spells with non-league teams Welling United and Tooting & Mitcham after leaving Charlton in 1995.
Managerial career
Gritt was named as joint player-manager of Charlton in 1991, alongside Alan Curbishley. In his four-year tenure, Gritt helped to lay the foundations for future successes under Curbishley, who succeeded him as sole manager in 1995. Several key players were debuted under the joint managers, including Lee Bowyer, John Robinson, Richard Rufus and Shaun Newton, and went on to be important components of Charlton's successful team of the late 1990s and early 2000s. Gritt was made manager of Brighton & Hove Albion in 1996, who were at the time eleven points adrift at the bottom of the Football League. He was able to turn Brighton's form around, and they successfully avoided relegation to the Conference on the final day of the 1996–97 season. Brighton were never in danger of relegation the following season, but the club's board had higher expectations and Gritt was fired in 1998. Nevertheless, Gritt is still fondly remembered by the Seagulls' supporters. Gritt later moved to Millwall and became reserve-team manager. In 2000, he had a short spell as caretaker manager of the Lions and was then assistant manager to Mark McGhee until 2003. In June 2004, Gritt returned to Charlton in the role of academy manager, a role he retained until 2010. From July 2011 to September 2012, Gritt was chief scout at Bournemouth. From June 2013 to October 2018, he was assistant manager at Ebbsfleet United, working with former Charlton team-mate Steve Brownand then, after a spell as chief scout, serving as assistant to Daryl McMahon. In August 2019, Gritt was again appointed assistant manager to McMahon, this time at Macclesfield Town. Both resigned on 2 January 2020, citing the club's crippling financial situation, with both subsequently joining Dagenham & Redbridge.
Gritt suffered a tragedy on 7 December 2002 when his 18-year-old daughter Hayley died as a result of cancer. Hayley, who had battled a brain tumour for 10 years, was a lifelong Charlton supporter and a season ticket holder at The Valley, even after her father's departure from the club in 1995. Gritt has been involved in numerous fundraising activities for cancer charities ever since.
