United Rugby Championship: Cardiff 6-22 Ospreys

Ospreys powered their way to a convincing win away against Cardiff in the United Rugby Championship (URC).

A penalty by Cardiff's Rhys Priestland provided the only points of a dismal, error-strewn first half.

Ospreys dominated the second, with Dewi Lake and Rhys Webb scoring two quickfire tries to put them 17-6 ahead.

Sam Parry crashed over for their third to keep alive hopes of qualifying for next season's European Champions Cup as the URC's highest-ranked Welsh side.

For Cardiff, meanwhile, this was another disappointing derby defeat following back-to-back losses against Scarlets.

Having beaten Leinster and Glasgow earlier this year, their season is beginning to peter out - whereas Ospreys still have plenty to play for.

They were bolstered by the return of Wales lock Alun Wyn Jones at Cardiff Arms Park, the totemic British and Irish Lions captain reaching yet another career milestone as he made his 250th appearance for his home region.

Jones was one of six Wales internationals in the Ospreys pack, who were close to providing the opening try after only two minutes, but hooker Lake was held up over the line at the back of a maul.

Cardiff wing Owen Lane was sin-binned for a deliberate knock-on soon afterwards, but Ospreys were unable to exploit their man advantage in a scrappy and scoreless opening quarter.

While the errors piled up and excitement levels flatlined, the first points of the match eventually came in the form of a 28th-minute penalty from Priestland.

Supporters finally had reason to leap to their feet when Cardiff number eight James Ratti carried explosively from his own 22 and into the Ospreys' half but, true to the match's disjointed nature, his offload to Tomos Williams went awry.

Centre Michael Collins became the second Ospreys player to be held up over the line in the final play of the first half but, after the break, points flowed more freely.

Priestland and Gareth Anscombe exchanged penalties before the latter kicked to the corner, setting up a driving maul from which Lake scored the game's first try.

Then just as Cardiff seemed to be building some attacking momentum, Priestland's pass was picked off by Webb and he sprinted clear from his own half and sauntered under the posts.

Ospreys scrum-half Rhys Webb has won 36 caps for Wales

In the space of 13 minutes, Ospreys had turned a 6-0 deficit into a 17-6 lead and they were close to extending it when former Cardiff wing Alex Cuthbert knocked on just a few metres short of the line.

It did not matter as Ospreys soon had their third try. Again it came from a line-out, but this time, instead of using the maul, the ball was worked to Webb and he popped it for replacement hooker Parry to touch down.

Ospreys ran out of time in their search for a fourth try and a bonus point, but their well-earned victory sets them up nicely for another derby next Saturday against Scarlets.

Cardiff director of rugby Dai Young: "It's obviously disappointing but it's a little bit the story of the last three or four weeks.

"You can't defend for 80 minutes, you can't give teams possession and territory for 80 minutes and that's what we're doing week after week, game after game.

"First and foremost, we're playing against a decent team. We know where their strengths are going to come but we have to be better ourselves. We had opportunities to fire our own shots and we kept handing the ball back to them.

"I can't remember too many times when we really stressed them. You're not going to beat any team if you can't get past three phases on 15 occasions. That's on us."

Ospreys head coach Toby Booth: "Three tries disallowed by the TMO... I understand that is part of the game, but with certainly two of them the offences that go on before them are mind blowing for me.

"I will go through the right channels and speak to them about that because I thought we were good for a bonus-point win today.

"The way we defended against a Cardiff team who like to play, especially at home, and to negate them to six points was a massive feather in the cap for the boys and the effort they've put in.

"Also it's poignant for Alun Wyn's 250th game. He's had some not-so-memorable milestones and it was important to give him and his family one a positive one. It's nice to celebrate one of your own with a victory."

Cardiff: Hallam Amos; Owen Lane, Rey Lee-Lo, Max Llewellyn, Theo Cabango; Rhys Priestland, Tomos Williams; Rhys Carre, Liam Belcher, Dmitri Arhip, Seb Davies, Rory Thornton, Shane Lewis-Hughes, Josh Navidi (capt), James Ratti.

Replacements: Kristian Dacey, Brad Thyer, Dillon Lewis, Matthew Screech, Ellis Jenkins, Lloyd Williams, Jarrod Evans, Matthew Morgan

Ospreys: Max Nagy; Alex Cuthbert, Michael Collins, Owen Watkin, Keelan Giles; Gareth Anscombe, Rhys Webb (capt); Gareth Thomas, Dewi Lake, Tomas Francis. Adam Beard, Alun Wyn Jones, Will Griffiths, Jac Morgan, Morgan Morris.

Replacements: Sam Parry. Nicky Smith, Tom Botha, Rhys Davies, Ethan Roots, Reuben Morgan-Williams.

Referee: Gianluca Gnecchi (FIR)

Assistant referees: Adam Jones, Jason Bessant (WRU)

TMO: Sean Brickell (WRU)