The new Magners League season got under way with a pulsating clash at Ravenhill, as Ulster edged out champions Ospreys 27-26.
A rollercoaster of an opening-night contest remained in the balance right until the final minute, as first-half tries from Stephen Ferris and Darren Cave set Ulster on their way to victory, while Niall O'Connor kicked five penalties and a conversion for a 17-point haul.
Ospreys had Dan Biggar firing on all cylinders, as the fly-half scored a try and kicked two conversions and four penalties - a 100 per cent kicking haul - to contribute 21 points.
Richard Fussell crossed for the visitors' other touchdown, but the Ospreys had to make do with a losing bonus point.
Biggar drew first blood for Ospreys with an early penalty which was matched by O'Connor seven minutes later.
O'Connor was then wide with his second penalty attempt after 17 minutes but a great charge into the Ospreys' 22 by new signing Pedrie Wannenburg led to Ulster putting a penalty into the corner.
From the line-out Rory Best's throw missed Johann Muller but when Jerry Collins failed to gather the overthrow, Ferris scooped up the ball and ran over unopposed. O'Connor slotted the conversion and Ulster were 10-3 up.
They extended their lead to 10 points when O'Connor landed a long-range penalty after the restart, but then Ospreys began to claw their way back.
First Biggar slotted a penalty after Ulster strayed offside and then, even with Nikki Walker sent to the sin-bin for taking out David McIlwhaine without the ball, Fussell went over in the left corner.
Biggar's excellent conversion tied the scores, but Ulster crept ahead again after Cave shook off the attempted tackle of Marty Holah for an unconverted score.
Biggar then kicked his fourth shot at goal from four attempts, after Bryan Young was penalised at a scrum to put Ulster 18-13 up at the break.
The hosts stretched their lead just after the restart with an O'Connor penalty but Ulster errors allowed the Ospreys back into the game when a poor pass from O'Connor to McIlwhaine was hacked downfield, before Biggar got to the ball first for a 42nd-minute try which he then converted to put Ospreys 23-21 ahead.
O'Connor was then wide with a long-range penalty before he put Ulster one point ahead with his fifth success from eight attempts after 53 minutes.
But the lead did not last as Biggar kept his 100 per cent kicking record intact to put Ospreys into a 26-24 lead after Ulster infringed.
But Ulster were not finished and after the Ospreys strayed in front of a kick ahead, O'Connor stepped up to slot over the final and ultimately match-winning penalty.
Tries: Ferris, CaveCon: O'Connor
Pens: O'Connor 5
Tries: Fussell, Biggar
Cons: Biggar 2
Pens: Biggar 4
Ulster: 15 Adam D'Arcy, 14 Tommy Seymour, 13 Darren Cave, 12 Ian Whitten, 11 David McIlwaine, 10 Niall O'Connor, 9 Paul Marshall, 8 Pedrie Wannenburg, 7 Willie Faloon, 6 Stephen Ferris, 5 Tim Barker, 4 Johan Muller, 3 Declan Fitzpatrick, 2 Rory Best (c), 1 Bryan Young.
Replacements: 16 Nigel Brady, 17 Tom Court, 18 Paddy McAllister, 19 Ryan Caldwell, 20 Robbie Diack, 21 I Porter, 22 Paddy Wallace, 23 Jonny Shiels
Ospreys: 15 Gareth Owen, 14 Nikki Walker, 13 Sonny Parker, 12 Andrew Bishop, 11 Richard Fussell, 10 Dan Biggar, 9 Jamie Nutbrown, 8 Jonathan Thomas, 7 Marty Holah, 6 Jerry Collins (c), 5 Ian Evans, 4 Ian Gough, 3 Craig Mitchell, 2 Mefin Davies, 1 Ryan Bevington.
Replacements: 16 Huw Bennett, 17 Paul James, 18 Cai Griffiths, 19 James Goode, 20 Ben Lewis, 21 Rhys Webb, 22 Lee Byrne, 23 Shane Williams.
Referee: Peter Allan (Scotland)