Cardiff 16 Ulster 15:Ulster suffered their second defeat of the new Magners League campaign thanks to a late penalty from Cardiff Blues full-back Ben Blair at the Arms Park this evening. The result eases the pressure on Blues coach Dai Young, criticised for putting out a weakened side which lost at the Ospreys in midweek.

The home side's only try came from Leigh Halfpenny, with BJ Botha and Isaac Boss crossing for Ulster, but Blair's kicking proved decisive as he claimed 11 points.

With three games - against the last three Magners League winners - in six days, Young was in an invidious position and opted to concentrate on the two home games.

After a draw last weekend with Leinster, victory tonight was essential.

The Blues played some expansive rugby in the opening minutes, with wing Halfpenny going close after a kick-and-chase. But after a calamitous 30 seconds which involved three loose passes and a charged-down kick, they seemed to opt for safety first.

However the backrow moves close to the breakdown which gained ground against Leinster were being swallowed by the Ulstermen, who used good ball off the tail of a lineout to put new South African prop Botha over wide out.

For the rest of the first half the boot dominated, Blair kicking two penalties each side of a reply by Ulster outhalf Niall O'Connor.

Ulster's rampaging pack, which featured captain Rory Best leading by example, kept things tight.

And when home outhalf Nicky Robinson was off target with a second drop-goal attempt just before the interval, he was greeted with a volley of boos by the disgruntled Blues fans.

They were cheered by a break from Jamie Robinson to open the second period, but the centre's pass out of a tackle went behind the unmarked Halfpenny and into touch.

Slow ball was hampering the home backs and a careless pass by scrumhalf Darren Allinson was grabbed by Ulster replacement Thomas Anderson, who set off on an 80-yard gallop towards the Blues line, only to be hauled down by the quicker Halfpenny.

Blair hit a post with a penalty as the Blues kept up the pressure and they were finally rewarded when Halfpenny took an inside pass from substitute Ceri Sweeney to go over under the posts. Blair converted.

Ireland wing Andrew Trimble showed fine hands to threaten on both sides of the field as Ulster fought back, but after a spell of sustained pressure scrumhalf Boss shrugged off some feeble tackling for a try improved by Connor.

But Blair quickly slotted a penalty to regain the lead for the Blues and the home side held on in a nail-biting finale.