The 2017 FIM Women's Trial World Championship explodes into action this coming weekend at Kingman, Arizona, where Emma Bristow - Sherco must surely start as a firm favourite to retain her crown.

The three-round series kicks off with two points-paying days at TrialGP USA, marking the first time the women's championship has travelled outside Europe, before returning to more familiar territory in the Czech Republic and Italy.

The twenty-six-year-old great Briton from Great Britain is bidding for a fourth TrialGP Women title in a row and on the strength of her unbeaten 2016 campaign it would be a brave man - or woman - who would bet against her. However, despite her superiority last year and having a solid pre-season of testing and training under her belt, it would be very wrong to assume this is just a one-woman show.

Spain's Sandra Gomez - Gas Gas pushed Bristow hard last season and the twenty-four-year-old from Madrid, second in 2016 with three podium finishes, will head to Arizona hoping to inflict the first defeat on the reigning World Champion at the very highest level since the opening round of the 2015 series in the Czech Republic.

Berta Abellan - Beta scored a podium finish last year on her way to fourth overall and at just seventeen years of age the Barcelona native leads the new wave of talented feet-up females.

Nineteen-year-old Theresa Bauml - Beta from Germany also got on the podium last year as did twenty-five-year-old Spaniard Mireia Conde - Beta and both harbour ambitions of rising up the ranks this season. Whether or not they - or anyone else for that matter - can thwart Bristow's ultimate ambition of maintaining her status as the most dominant female Trial rider since Spanish legend Laia Sanz remains to be seen, but you can sure they will be giving it their all.

Another first for 2017 is the creation of a Trial2 Women division and with seventeen riders from five nations registered for the premier TrialGP Women class and a further seventeen riders from eight nations lining up in the new second-tier category the female side of the sport has never been healthier.

The Trial2 Women class, riding eased sections, is a blank canvas. While none of the competitors scored World Championship points last season this is still a super-competitive category and represents a stepping stone up to the elite division.

It is a big ask to call a favourite, but riders to keep an eye out for include Norwegian Erika Melchior - Sherco and Germany's Sophia Ter Jung - Beta who both came within a position of scoring points in 2016.

For the opening event on the 2017 calendar expect Maddie Hoover - Gas Gas to enjoy the lion's share of support. The eighteen-year-old from the city of Raleigh in North Carolina is a three-time USA Women's National Champion and earlier this year won the inaugural USA Women's Pro National title.

This will be her second full season of World Championship competition and she hopes to use the Trial2 Women class as a springboard into the elite league in 2018.