Tommy Bowe loses the ball in tricky weather conditions at the Liberty Stadium.
Jonathan Humphreys insists the Ospreys are hitting form at just the right time after regaining top spot in the Magners League.
Scotland wing Nikki Walker bagged a brace of first-half tries before skipper Ryan Jones sealed an emphatic Welsh derby victory over Cardiff Blues at the Liberty Stadium.
The result puts the Ospreys two points clear of Glasgow Warriors at the summit of the table and in good spirits ahead of a crunch month which includes mammoth Heineken Cup ties against Clermont Auvergne and Leicester Tigers.
Humphreys said: "It's good to be top of the league and that's where we want to be. We appreciate everyone else has games coming up but with the changes we made to our game, we always felt December and January would be defining months for us.
"The structure was good as was our defence. There are still things to work on but we believe things are coming right for us and our form is getting towards where we want it to be.
"We have to be in good shape going into the Heineken Cup and continue our momentum before facing Clermont."
Man-of-the-match Dan Biggar opened the scoring with a deft 12th minute drop goal on the way to an 11-point personal haul before Walker crossed at the end of the opening quarter.
Then Walker doubled his try count from close-range in the left corner following a neat break by fly-half Biggar and Jones added a third with a try just after the hour mark to leave the Blues white-washed.
Humphreys added: "We're pleased with the performance but it is disappointing that we didn't get the bonus point considering how early we scored the third try.
"We're delighted to keep them to nil and it's nice to achieve that against anybody. But it wasn't easy. There are a lot of battered and bruised bodies in the dressing room."
Blues coach Dai Young offered no excuses as his side are still searching for their away success in the league this season.
Young said: "Sometimes you have to hold your hands and say we were beaten by a far better side. It was a disappointing performance and the Ospreys controlled the field."
The annual Women's club launch was held at the Wales Centre of Excellence where National Women's Head Coach and Programme Lead Rhys Edwards, Competition Secretary Adrian Howell and Cardiff Met player Ffion Jones express eagerness for the new campaign to get under way.
WRU TV follows Wales' RWC training squad on day one of their camp in North Wales. The squad were greeted to an official welcome in Colwyn Bay and then headed for an afternoon of team building at ZipWorld