Arai entered professional football with Albirex Niigata after graduating from Rissho University in 2001 but was unable to hold on to the first team place although he played 20 league games for Albirex Niigata in his first season.
[1] He was on loan to Albirex Niigata FC (Singapore) in 2004 and in 2006 he secured a permanent move to Singapore Armed Forces FC.
He is also the second Japanese player, after his Singapore Armed Forces FC teammate Masahiro Fukasawa, to play in the AFC Champions League for a non-Japanese club.
In November 2009, Kenji joined SC Goa.
Albirex Niigata Singapore Armed Forces