Ulster lock Matt McCullough was bitterly disappointment with his side’s performance as they went down by six points at Edinburgh in the Magners League.

Ulster were hoping to build on last week’s bonus point victory in Munster but failed to recapture that form as they were outscored by two tries to none.

“We weren’t at the races for the first 20 minutes and gave Edinburgh a 15-point start before any of us had made an impact,” stated McCullough.

“It was a very poor performance especially after Limerick where we had reached an acceptable performance.

“This is a step backwards when we wanted to take another step forward.

“We weren’t surprised by anything that Edinburgh did, we have to be honest with ourselves as players and hold our hands up and say that wasn’t good enough.

“As a squad we were on a high and done something great last week, but we didn’t channel that renewed energy into our performance.”

“The great teams win week in and week out so we have to look at ourselves within the squad and use these performances as a tool to become a better team.”

Meanwhile, centre Lifeimi Mafi scored one try and set up another as Munster avoided a third straight defeat to leap-frog the Ospreys and go top of the Magners League, defeating the Welsh side 25-21.

Home outside-half James Hook kicked seven penalties to earn his side a losing bonus point, but the defeat will only fuel growing speculation that the Ospreys, who decided to rest Wales trio Ryan Jones, Gavin Henson and Adam Jones, are about to appoint Scott Johnson as head coach.

The Ospreys, who welcomed back Shane Williams from a shoulder injury, had their moments, especially when Andrew Bishop broke through two tackles, but kept losing the ball or being pinned back in their own half with penalty kicks to touch.

Munster scrum-half Thomas O’Leary scored eight unanswered points to settle the contest.