It's another wet evening in early November and Maggie Alphonsi is training, an hour before everyone else, at Oakwood, north London. Occasionally she slips on the churned surface of the well-used turf and her perfectly-formed calves get caked in mud. She's a muscular presence, but a feminine one, and entirely at home on the pitch. Alphonsi, 25, is the Saracens and England openside flanker and former IRB player of the year. A Saracens player for the last decade, Alphonsi is one of the best female rugby players in the world right now, and is described by her Saracens coach, Amanda Bennett, as "a wonderful physical specimen; her breakdown skills, her tackle technique, her physique, her attitude - it doesn't get any better."

It probably helps that Alphonsi plays for the most successful women's rugby team in the history of the game in the UK. Last year Saracens won the Premiership for the third consecutive year and they boast other England internationals including centre Rachel Burford and hooker Amy Garnett. But, despite playing regularly for their country, these are not household names because women's rugby - entirely dependent on Sport England for its financial viability - is only slowly marking a place for itself on the sporting map.

There are 500 women's rugby clubs registered with the RFUW and the governing body estimates that around 20,000 women and girls in the UK play the sport. "It's definitely the biggest female rugby-playing population in the world by a long shot," says RFUW managing director Rosie Williams. In terms of media attention and progress towards becoming professional, though, it is a poor relation to women's football, which has press and television coverage, and the anticipation of contracts for England players when the structure of the game is revamped next year.

Yet rugby's profile could be on the rise. England have beaten competition from South Africa, Kazakhstan and Germany to win the right to host the women's rugby World Cup in 2010, and those within the sport are expecting great things from the national team - runners up at the last World Cup in Canada in 2006 and current Six Nations champions - on home turf. The RFUW expects live TV coverage of all England games, the semi-finals and the final, and Bennett, a Welshwoman who has put those allegiances aside to coach England squads in the past, calls it "a massive opportunity".

"It will bring the game to the people," she says. "I expect it to be in people's living rooms and hopefully there'll be good news stories ... what's really important is that the governing body looks not only to win it, [but also has] a development plan that can manage if there's a massive surge in women wanting to play rugby."

The prospects are good for women's rugby on a national level, but things do not look as rosy for the clubs. Rugby faces the same fundamental difficulties that afflict most women's team sports: a lack of depth, with teams at the bottom of the league utterly unable to compete; a perceived low skill level; and, most damagingly, little outside interest in a sport that struggles to provide potential fans with a sense of occasion and individuals to adulate.

Saracens have already won the most difficult fixture of their season, 15-18 away at fierce rivals Wasps, and teams permanently lower down the division are unlikely to generate any shocks. Saracens are unbeaten in the league, home and away, since 2005 - eat your heart out Chelsea. It may not be a challenge to keep the players interested in winning, but it is difficult for spectators to get excited about watching the same team win in perpetuity.

Every sport has to deal with disparities of wealth and success but in some the divide is most acute in women's rugby. "I agree it needs to be more competitive," admits Bennett. "There's little point in Saracens having all the best players in the country, some of whom are the best players in the world, turning out on a Sunday and winning 80-0 ... there are teams that have never beaten us and they won't beat us for a long time yet."

People are understandably dubious of the skill level within women's rugby - if football is a man's game, rugby is a real man's game, so how can women, with their weaker upper bodies, play it? Senior England players in the Saracens squad are coached by the men's academy, providing a good test of their ball-breaking abilities, while players and coaches alike are adamant that there are no half measures in the women's game, no giggles at dropped passes, no holding hands in the scrum, no snuggling up to tackle pads.

Burford, an ambassador for Nike's Here I Am campaign, which aims to challenge the low appreciation of sportswomen and encourage a new generation of female athletes, says there are "absolutely no differences between the games - same ball, same size pitch", and while that might seem slightly naïve, newcomers to the sport may be surprised at the physicality and aggression on show, scrums lined up like ordnances, players hurling themselves into tackles with the ferocity of lionesses defending their cubs. "I think they'll see an incredible skill level that sometimes you don't see in the men's game because of the physicality of the men's game," says the RFUW's Williams. "We play very open, the ball is in play a lot and set pieces are important but not 100% important."

"I like to think [the women's game] is more technical," says Alphonsi, "but if people want to see brute force, want to see a bit of a smash, then the good thing about the women's game is that it provides all that. Don't watch it as a women's match or a men's match. Respect it in its own entirety. It's not about that there are women playing, it's not about how long that pass was, it's about a great game."

But skill is not what makes a sport professional; money is, and money comes from TV coverage, which relies on having an audience willing to pay to watch. "The money will only come once it becomes a spectacle," says Alphonsi. "If it's not on TV, it's not interesting. I look at most women's sports and the money's not there and that's a shame." "I'm not sure that any women's team sport is ready to be professional," adds Williams. "Until television companies are paying enormous amounts of money to [show] women's sport there will be very few professional women athletes."

For women's rugby to flourish and inch towards parity with the finances on offer to sportsmen, it needs to break away from allegiances with fellow men's teams and start to create its own history. Fans don't watch their team simply because of the quality on offer - they're there because, in an intangible way, it matters to them whether their team win and because it ruins the weekend if they lose.

Those are emotions that women's team sports can't yet tap into on a club level. Where's the sense of occasion standing in a field watching a game with six parents, three passersby and a dog? Women's sport is mercifully devoid of the cult of celebrity that devours top sportsmen but thatshouldn't mean it has to lack stars. The World Cup could encourage an appreciation of female players - with biceps to rival Danny Cipriani and puppy-bearing hips - simply because of their ability to play the game. If England get to the final, and generate some flag-waving along the way, it might even get interesting.