Crumpton (43), a nurse in the post-anaesthetic unit at Dunedin Hospital, won the event in 2010 in 2hr 45min 49sec, when it doubled as the New Zealand championships.
Crumpton finished fourth last year in 2hr 52min 18sec. Her best performance this year was her second placing at the Wellington marathon in 2hr 55min 4sec.
Her main opposition will come from former champions Ady Ngawati (Whangarei) who won the Auckland title in 2007 and 2008 and Lisa Robertson (Auckland) who won in 2011, in 2hr 41min 56sec.
Robertson (30) is ranked third in New Zealand this year with her time of 2hr 51min 24sec when she finished 12th at the Gold Coast marathon in July.
Other contenders for the title include Kirstin Molloy (Australia), who was third in 2011, and Kelly Parlane (Auckland), who was third in the Christchurch marathon in 2009.
Crumpton won her first marathon at Christchurch in 2002 and has won 15 marathons in her long career. This includes New Zealand titles in 2005, 2009, 2010 and this year.
Her fastest time of 2hr 37min 3sec was run at the world championships in 2005, when she finished 33rd. She ran 2hr 41min 31sec at the world championships in Berlin in 2009.
