The Ospreys have secured their first European Cup win of the season after a superb 27-16 victory over English rugby union leaders London Irish in Swansea on Friday.

Ospreys wing Tommy Bowe scored a fourth-minute try and Dan Biggar kicked four first-half penalties, but a breakaway try from Sailosi Tagicakibau kept the visitors in touch.

Welsh international Shane Williams took the game away from Irish after a magnificent chip and chase allowed him to cross the try-line in the corner in the 53rd minute to secure an important win.

"I had been finding it really difficult to get involved in games this season but I felt sharp tonight," said Williams.

"I just wanted a crack, to be honest. I feel pretty good.

"It was a very tough game and there was a lot of pressure on us to play well. It would have been doom and gloom in Wales had we lost."

The hosts had to see out the match without sin-binned flanker Jerry Collins, who was punished for going over the top, but held on for a victory that prolongs their unbeaten five-year run at home in European competition.

Toulon, who beat Ospreys 19-14 in their opening match, can now go top of Pool 3 if they win at Irish side Munster on Saturday.

In the other game on Friday, French side Castres secured a 27-20 win at home to Cardiff Blues in Pool 1 after storming into a 27-6 half-time lead thanks to a pair of tries from wingers Vincent Inigo and Marc Andreu.

The Welsh side trailed 27-13 with minutes to play but salvaged a valuable losing bonus point when replacement prop Scott Andrews crossed in the final minute and Ceri Sweeney sank the resulting conversion.

"It was a good performance from our perspective," said Castres full-back Romain Teulet.

"At 27-6 we might have thought that they'd give up but it wasn't the case. Cardiff are a team who always play with lots of intensity and rhythm.

"In the end, both teams had a half each. What we have to take from this is the collective desire of the squad to pull together."

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