Simpson made his Gunners bow in the League Cup aged 19 - making him a late starter by The Gunners' standards
Tottenham born but Arsenal raised, Simpson is a product of Arsenal's youth set up, and spent 2007/08 on loan at London rivals Millwall.
41 League One matches and six goals later, Simpson returned north of the river with the aim of establishing himself in Arsene Wenger's first team.
The powerful and athletic forward didn't have to wait too much longer for that opportunity, making his senior Gunners debut in the 6-0 Carling Cup rout of Sheffield United in September 2008, having impressed on the pre-season tour of Austria.
Simpson made headlines with two goals in Arsenal's 3-0 win over fellow Premier League side Wigan in the Carling Cup 4th round two months later.
Regardless of whether he can cement a regular place in the team, Simpson will go down in history as the first player to score a competitive hat-trick at the Emirates, in an FA Youth Cup match against Cardiff in 2007.