AUSTRALIA'S elite women's cross-country champion Peta Mullens is adamant if Canberra's Bec Henderson had been allowed to race in the open class, she would have been the new national champion instead.
But International Cycling Union regulations meant Henderson had to ride in the under-23s, which she won comfortably by more than 20 minutes.
She stopped the clock in one hour, nine minutes, 44.1 seconds after four laps of the six-kilometre course at Stromlo Forest Park.
Such was her dominance, she led the elite field - which did one extra lap - by about 30 seconds when she finished.
Mullens said Henderson's efforts justified her spot at last year's London Olympic Games.
''There's no doubt she would've won the race today if she was able to race elite,'' Mullens said.
''She wanted to go out here to prove she deserved her selection last year and I think there's no doubt in anybody's mind that she certainly did … she pumped us by 30 seconds with a lap to go.
''There was no doubt in my mind [she would've won], I was glad she was in under-23s so she didn't take the title from me.''
Mullens, a Tiger Trek MTB racing teammate of Henderson, went out to prove her doubters wrong.
The Stromlo course was not expected to suit the endurance rider, who held off last year's winner Jenni King.
''It was technical for me, I think everybody would've said that it wasn't my course and it probably wasn't going to be my day, but I was glad to prove those people wrong and take the title,'' she said.
Henderson has been racing in the elite class in the national cross-country series, winning the round at Thredbo two weeks ago.
But since the national championships are a UCI event, she had to ride in her age group.
She was happy to do so on the international stage, but thought she might benefit from riding at elite level in Australia.
''The depth in Australia isn't super-great so it's a shame [I can't ride at elite level], but I'm certainly happy racing under-23s when we race in the World Cup overseas,'' Henderson said.
''They [the elite women] certainly bring out the best in you and you race against the best women in Australia, it makes you push harder and brings out the best in you and pushes you to your limits.''
Henderson's boyfriend and coach Dan McConnell finished runner-up to South Australian Chris Jongewaard in the men's elite race. McConnell was returning from a hand injury and wasn't expecting to win.
He finished one minute, 1.1 seconds behind Jongewaard (one hour, 29 minutes, 53.3 seconds), who won his sixth national title in nine years.
In other news, Caroline Buchanan qualified as the fastest woman in the elite women's downhill event. Her time of two minutes, 46.05 seconds narrowly edged out Tracey Hannah by just three one-hundredths of a second.
The final of both events will be held from 4pm on Sunday.
AT A GLANCE
Australian National Mountain Bike Championships: Cross country - elite women: 1. Peta Mullens, 2. Jenni King, 3. Rowena Fry; Under-23 women: 1. Bec Henderson, 2. Clea O'Brien, 3. Rosemary Stewart; Elite men: 1. Chris Jongewaard, 2. Daniel McConnell, 3. Sid Taberlay.