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."
On the day the Wales U20 squad for the Six Nations is revealed, WRU Head of Rugby Performance Geraint John discusses the priorities of the Wales U20 programme, and moves being undertaken to make it easier for Welsh Exiles to be part of the WRU pathway - and to help keep Welsh qualified players in Wales
It was a double celebration for Wales and Ospreys scrum-half Rhys Webb when he called at the home of Welsh rugby to help commemorate the first anniversary of Principality Stadium and his return to fitness this weekend ahead of the RBS 6 Nations.
Prior to their departure to Wellington for the next leg of the World Series, Wales trained with England and Ireland. WRU TV caught up with Owen Jenkins who revealed the 'buzzword' which is driving the Wales squad on.
Wales head coach Rob Howley explains his decision to change the captaincy of the national side with Ospreys second row Alun Wyn Jones taking over from Sam Warburton for the forthcoming RBS 6 Nations. Howley is hoping his decision will allow Warburton to rediscover his 'mojo'.
How do you follow a dancing hippopotamus - the Ospreys wheelchair rugby team has just the 'oneness' to do it say the BBC! For a decade the sight of a herd of hippos synchronised swimming around their own private blue lagoon, has lit up our television screens at regular intervals between favourite BBC One shows. But now the nation's most watched channel has relinquished its famous amphibious mammals in favour of a new show-reel which includes the Ospreys wheelchair rugby team.
Head coach Rowland Phillips and key front rower Carys Phillips look ahead to games against Spain and Ireland as Wales Women ramp up their preparations for the forthcoming Six Nations. The two warm-up games are a 'massive opportunity to refine the squad' according to the Welsh camp.
Martyn Phillips has discussed details of the newly published 'Strategy for Welsh Rugby' which puts in black and white terms the plans and direction of the governing body of the national sport in Wales for the next decade.
WRU chief executive Martyn Phillips has urged Welsh rugby fans to follow in the footsteps of their soccer counterparts at last summer's Euro Championship by backing their team to the hilt in the upcoming RBS 6 Nations campaign.
Chief executive Martyn Phillips has highlighted the plans for Wales to become a breeding ground for national and elite club rugby coaches, which are contained in the WRU's 10-year 'Strategy for Welsh Rugby'.
Andrew Coombs is enjoying his new role as Nelson forwards coach. The former Dragons and Wales lock has big ambitions to become a professional coach but feels it's important to learn the ropes in grassroots rugby and where better than his home club Nelson, with friends and family close to hand.
Students at Brynllywarch Hall School, near Newtown, have transformed their own lives, and are now having a positive impact on others through rugby. The sport has had a life-changing effect on the well-being of the students who are now delivering rugby sessions to local primary schools and playing for a new mixed ability side
Wales reached their first semi-final since 2013 in the opening round of this season's HSBC World Rugby Sevens Series in Dubai. WRU TV's Graeme Gillespie recaps on what proved to be an eventful tournament
Wales and Ospreys back row James King, who came through the North Wales age grade system, nominated North Wales Regional Community Rugby Manager Marc Roberts, in the WRU's 'Diolch' initiative where squad players thanked those who played a part in their rise to the top.
Beating Merthyr has boosted Carmarthen Quins hopes of reaching a top eight spot in the Principality Premiership. Quins captain Haydn Pugh is delighted with his team's progress and is determined that everyone from the Under 6s through to the senior team, enjoys the ride.