Blenheim doctor Harriet Harper is expected to dominate the women's downhill races at the New Zealand mountain bike championships in Dunedin this weekend.
She has been the form rider in the women's races this season and won the New Zealand Cup during the national series.
Harper (29) first made her mark on the international scene when she finished 11th at a world cup in Quebec in 2008.
A year later, she finished 16th at the world championships in Canberra and was the first New Zealander to finish.
Harper moved to a new level last year when she won the New Zealand and Oceania titles.
She dominated the elite women's race at the Oceania championships in Dunedin and won by nine seconds in 3min 07.36sec.
Harper, who studied at the University of Otago, started mountain biking when she was a medical student in 2004.
She will be challenged by Amy Laird (Christchurch), who took a break from downhill racing over the past two years to concentrate on cross-country events.
Laird has returned to downhill racing this year but suffered a setback when she broke her collarbone in her first race at Tauranga.
Swiss international Emilie Seigenthaler has the ability to challenge Harper but it would not matter, because she is not eligible to win the title.
The men's downhill title is wide open, with three riders ranked in the world top 15 competing.
Sam Blenkinsop (Wanganui) is ranked fourth, Cameron Cole (Christchurch) eighth and Justin Leov (Dunedin) 15th.
Blenkinsop (22) has been the form rider this season and won the New Zealand Cup.
Cole (23) should not be underestimated, because he likes racing in Dunedin and won the Oceania title on the Signal Hill course last year.
He won in 2min 39.15sec and was the first rider to break the 2min 40sec barrier on the course.
Leov (26) turned professional in 2004 and is the most experienced New Zealand downhill racer.
If he can reproduce his 2009 form, Leov will be a strong contender for the title.
The other downhill riders who could cause an upset include Brook McDonald (Napier) and Matt Scoles (Alexandra).
Last year's champion, Wyn Masters (New Plymouth), is on the sideline with a broken arm.
Christchurch lawyer Rosara Joseph is the favourite to win the women's cross-country event ahead of Karen Hamlen (Whakatane), Samara Shephard (Rotorua) and Erin Greene (Otago) on the Forrester Park course.
Joseph (29) won the silver medal at the Commonwealth Games in 2006 and was ninth at the Beijing Olympic Games in 2008.
She took a break from serious mountain biking when she completed her PhD in law on a Rhodes Scholarship at Oxford University.
Joseph is now back on her bike and has the potential to reach the podium at the London Olympic Games next year.
Dirk Peters (Rotorua) competed in only two of the four events in this season's national series but won the races at Napier and Nelson that counted for UCI points.
Peters (19), who is putting his main emphasis on World Cup races overseas this year, has targeted certain races on the domestic scene.
Mike Northcote (Tokoroa), an old hand in the sport, won the New Zealand title at Wellington last year and should not be under-estimated.
This is the first time the national mountain biking championships have been held in Dunedin.
The city was awarded the event after the successful Oceania championships last year.
The cross-country course is similar to that used for the Oceania championships last year but there are significant changes to the downhill course on Signal Hill.