Cardiff Blues lost their stranglehold over Ulster, which stretched back seven games to October, 2006, as they were beaten 37-15 at home in the Magners League.
The Blues were leading 15-8 at the break thanks to tries from Casey Laulala and Tom James, but then fell apart in the second half as they conceded four tries and 29 unanswered points.
Ulster's teenage wing Craig Gilroy scored a try in each half and his second touchdown, which began at a quickly taken line-out in the visitors' 22, turned the game on its head.
It also came in the middle of a 15 point burst from Ulster in the space of four minutes and set them on their way to a first bonus point victory of the season.
The defeat means the Blues lose their grip on third place in the Magners League table, Ulster moving ahead of them, and puts added pressure on next weekend's home clash with Glasgow Warriors.
Earlier in the weekend a last gasp try from replacement scrum half Jamie Nutbrown earned the Ospreys an important 16-15 victory over Connacht in Galwey. That triumph included a drop goal from the 18-year-old Matthew Morgan on his Magners League debut.
But there wasn't any luck for the Dragons in Ireland as they conceded four tries in a 27-6 defeat against Leinster in Dublin.
Wales U20 duo Leon Brown and Lloyd Lewis face a busy couple of weeks ahead. Not only will they have a Junior World Championship to take part in, they are both sitting A Level exams during the competition.
Wales U20 face a tough group in the Junior World Championship with France, England and Japan lying in wait but Attack coach Jason Strange and back rower Tom Phillips are looking forward to the campaign ahead.
Angus O'Brien has quickly settled into the Wales Sevens squad after solid performances in Hong Kong and Japan. With two rounds remaining in Glasgow and Twickenham on the World Series, WRU TV's Graeme Gillespie chats to the rising star.
Wales winger Luke Morgan has established himself as one of the deadliest finishers on the Sevens World Series. WRU TV's Graeme Gillespie catches up with him on the eve of this weekend's round in Glasgow.
All roads lead to Cardiff on Sunday for the SSE SWALEC Finals Day at the Millennium Stadium. Cambrian Welfare tackle Ystradgynlais in the Bowl final, Ystrad Rhondda play Newcastle Emlyn in the Plate final while defending champions Pontypridd face Bridgend in the Cup final.
WRU Chief Executive Roger Lewis, Deputy Minister for Culture, Sport and Tourism Ken Skates and WRU Chairman Gareth Davies earlier this week launched a new competition in conjunction with the WRU unveiling its archive room.
Welsh players and management joined Deputy Minister for Sport Ken Skates at the Pierhead Building, Cardiff Bay earlier this week to reveal the Union's pioneering school-club hub initiative has been so successful the project will now almost double the scale of the original project.
The Scarlets, Newport Gwent Dragons, Cardiff Blues and the Ospreys look ahead to Judgement Day III which sees the Blues take on the Ospreys (2.30) and the Dragons tackle the Scarlets (4.45pm) at the Millennium Stadium tomorrow afternoon.
Ystradgynlais and Ynysddu played out a titanic struggle at Taffs Well in the SSE SWALEC Bowl semi-final. At the end of the game neither team could be separated after a 15-15 stalemate but Ystradgynlais go through on try count.