Wales fly-half James Hook helped himself to 17 points as the Ospreys, who rested a number of players ahead of their European encounter with Saracens, proved too strong for a game Ulster side at the Liberty Stadium.

The Ospreys were edged out 17-16 in Belfast back in September but buoyed by their qualification for the EDF Energy Cup final, Lyn Jones’ side comfortably saw off Ulster to make it nine wins in their last ten matches in all competitions.

The Welsh region’s strength in depth was all too obvious as they made nine changes to the side that started last Saturday’s EDF Energy Cup semi-final success over Saracens.

Jones left out two very influential back rowers in Marty Holah and Wales’ Grand Slam-winning captain Ryan Jones, with Ben Lewis and Filo Tiatia, the skipper on the night, filling in.

Ulster welcomed back Matt McCullough, Isaac Boss, Kieron Dawson and Bryan Young into the starting line-up, after last weekend’s poor showing away to Munster.

Hurt by that record league defeat, Ulster were clearly fired-up in coach Matt Williams’ fourth game in charge.

They had all the early pressure, including two scrums from five metres out, but could not convert their dominance into points with fly-half Niall O’Connor also missing a penalty kick.

Ospreys number 10 Hook managed to raise the touch judges’ flags with a fine 15th-minute penalty goal.

Returning man Dawson was penalised soon after for not rolling away in the tackle, however Hook watched his penalty attempt bounce back off the post.

Referee Peter Allan began to lose patience with Ulster’s efforts to slow up the Ospreys’ ruck ball and prop Tom Court paid the price in the 20th-minute when he was sin-binned for not rolling away.

Two tries in the space of three minutes followed as the reigning league champions picked off their chances at will.

Ulster were badly caught out in the 21st-minute when Ian Gough’s lineout take had flanker Lewis breaking free into the visitors’ 22 and a quick feed out to Hook saw him beat three men to cross close to the posts. The stand-off converted for a 10-0 score-line.

The Ospreys added five more points when Ulster were cut open again. The ball was fed out for winger Nikki Walker to dart past the covering Justin Harrison and Bryn Cunningham and make the line.

Television match official Hugh Watkins confirmed the grounding for Walker’s score and he was also involved when ruling over Ulster openside Dawson’s try, three minutes before half-time.

Williams’ men got themselves back in contention and ironically the try was created by Tommy Bowe, who will be playing his rugby in Swansea next season.

Bowe sliced through, bringing play into the hosts’ 22 before offloading for the supporting Dawson to gather and touch down.

O’Connor converted and that remained the game’s most recent score until a 66th-minute penalty from Hook. Both O’Connor and his kicking counterpart had missed place kick, early on in the second half.

Hook did bisect the posts after the hour mark and then Shane Williams, Wales’ recording-breaking wide man, took over in the final ten minutes.

He was teed up by Jonny Vaughton, after some neat passing and inter-linking, for his first try which Hook easily converted for 25-7.

Williams, displaying his trademark fancy footwork, won a kick and chase for his second try, the Ospreys’ bonus point-clinching score.

All that left Ulster with their third defeat in four meetings with the Ospreys this season and much to ponder ahead of bottom side Connacht’s visit to Ravenhill in a couple of weeks’ time.