Gary Alexander was a hugely-popular figure at St James’ Park during his one-season stay on loan from West Ham United in 1999/2000 when he scored sixteen times in the league. He went on to enjoy a long professional career perhaps being best-known for his time at Leyton Orient.

Prior to his time at City, Gary had bided his time in the Hammers' reserve team. But it was at Exeter that his career really took off. Making his debut against Rotherham United in August 1999, Gary scored his first goal against Mansfield on 30 August 1999. This was the first of sixteen league goals as he lit up an otherwise dismal season for Exeter who ended in 21st place. Gary was to score two goals in a game on three occasions and also add one in the FA Cup and two in the Football League Trophy. Such goalscoring exploits meant Gary was Exeter’s player of the year in his sole season with the club.  

Although Gary was never to warrant a place in West Ham’s first-team, his form at Exeter earned him a £300,000 move to Swindon Town in July 2000. However, his stay at the County Ground didn’t prove to be a great success and he was on the move to Hull City a year later for a fee of £160,000. In his first season with the Tigers he netted 23 goals but in January 2003 he moved back to East London by signing for Leyton Orient. Gary scored in no fewer than nine successive matches for them in 2005-06 and after rejecting a new deal with Orient in May 2007, having scored 52 goals in 165 league starts, Gary joined Millwall who he had supported as a boy. After three seasons at the New Den, scoring 25 league and cup goals, Gary signed for Brentford in August 2010 and moved on loan to Crawley Town in March 2012 eventually making the move permanent later that year. After scoring 6 goals in 32 appearances for Crawley, Gary joined Burton Albion in 2014. 

With Gary’s stay at Burton proving to be short-lived he made the move back to his home patch with non-league Greenwich Borough where he was later manager. He left the club in January 2018 citing "financial constraints" and, after playing a couple of games for Chatham, Gary took up the role of Assistant Manager at Ashford United. He was sacked by Ashford in November 2018 but, after scouting for Millwall, he was appointed manager of Glebe in September 2019 before a spell as interim assistant manager of Isthmian League Cray Wanderers until March 2022. Later returning to football as director of football with Erith and Belvedere, he took charge of the club's first-team in February 2026.