|Ospreys (0) 13|
|Tries: Jones Cons: Davies Pens: Davies (2)|
|Cardiff Blues (3) 6|
|Pens: J Evans (2)|
Ospreys staged a second-half comeback to see off Cardiff Blues at wet and windy Liberty Stadium.
The home team trailed 6-0 to two Jarrod Evans penalties after an hour, but Alun Wyn Jones' try turned the tide.
Fly-half Sam Davies converted, kicked two penalties and gave a superb display of tactical kicking after replacing the injured Dan Biggar at half-time.
Blues lost Wales captain Sam Warburton, who limped off with an ankle injury during the first half.
Neither injury looked serious, and the irony for the Ospreys was that Davies' kicking was more effective than Biggar's had been in the opening half - so much so that he was named man of the match.
Not a day for running rugby
Heavy rain and strong wind dictated tactics, with both teams opting to either kick or attack close to the breakdown.
Ospreys dominated first-half possession but found the Blues' defence in no mood to concede ground, with Lou Reed, Manoa Vosawai and Ray Lee-Lo cutting down anything in a black shirt.
When they did make ground into Ospreys territory, Blues earned two penalties, with Evans kicking the first but missing a second just before the interval.
Ospreys spurned their one kickable penalty in the opening period, opting instead to kick for the corner where again the Blues were unyielding.
Blues flanker Warburton limped off midway through the half with an ankle injury and his Wales team-mate, Ospreys fly-half Biggar, did not come out for the second half after struggling with a back injury through most of the first.
Evans was on target with his second penalty after 50 minutes, but it spurred the Ospreys into life.
Blues repelled the first wave when Justin Tipuric's quick penalty came to nothing.
But Blues failed to clear their lines properly, and Jones rounded off a series of forward rumbles when he drove over from close-range near the posts.
Davies made no mistake with the conversion and punished Blues indiscretions with two successful penalties.
However, it was the 22-year-old's tactical play which really hurt the visitors.
With Jones and Tipuric leading an impressive forward display, Davies pinned the Blues into the corners as the rain lashed across the Liberty Stadium.
Blues battled gamely in a final attack which went through more than 30 phases, but ultimately foundered on a resolute home defence.
Ospreys: Dan Evans; Tom Grabham, Jonathan Spratt, Hanno Dirksen, Eli Walker; Dan Biggar, Brendon Leonard; Ryan Bevington, Sam Parry, Dmitri Arhip, Alun Wyn Jones (capt), Rory Thornton, Dan Lydiate, Justin Tipuric, Dan Baker.
Replacements: Scott Otten, Nicky Smith, Aaron Jarvis, Lloyd Ashley, James King, Tom Habberfield, Sam Davies, Ben John.
Cardiff Blues: Dan Fish; Blaine Scully, Ray Lee-Lo, Gavin Evans, Tom James; Jarrod Evans, Lloyd Williams; Gethin Jenkins (capt), Kristian Dacey, Taufa'ao Filise, Lou Reed, James Down, Josh Turnbull, Manoa Vosawai, Sam Warburton.
Replacements: Ethan Lewis, Sam Hobbs, Craig Mitchell, Jarred Hoeata, MacAuley Cook, Tavis Knoyle, Gareth Davies, Tom Isaacs.
Referee: Nigel Owens (Wales)
Assistant referees: Leighton Hodges, Wayne Davies (Wales)
Citing commissioner: Aurwel Morgan (Wales)
TMO: Gareth Simmonds (Wales)