Ian Humphreys scored all Ulster's points as they fought back to beat Clermont Auvergne in a tense Heineken Cup opener at Ravenhill.
Clermont controlled the early exchanges and Noa Nakaitaci's sixth-minute try and two David Skrela penalties helped them lead 11-6 at half-time.
Humphreys cut Clermont's lead with a 51st-minute penalty.
After a scoring lull, Adam D'Arcy's brilliant break set up Humphreys to score the decisive 70th-minute try.
Clermont dominated the early exchanges with Morgan Parra missing a straightforward penalty in the second minute.
The early Clermont pressure paid off with Nakaitaci's sixth-minute try after a charging Lee Byrne had brushed off Andrew Trimble's attempted tackle.
Parra missed the conversion but Clermont were looking comfortably the better team - even though Ulster were bossing the scrum.
Humphreys did open Ulster's account in the 12th minute after a second Clermont scrum collapse but Tom Court's infringement in open play soon gifted three points to Skrela, who had assumed the kicking duties after Parra's early misses.
After their poor opening quarter, Paul Marshall's quick tap-penalty seemed set to result in an Ulster try but Wesley Fofana somehow managed to make an interception as the home side seemed to have numbers out wide.
Ulster were finally beginning to gain a foothold in terms of possession but the Clermont defence was not being put under major pressure.
Skrela extended Clermont's lead two minutes before the interval but Trimble's brave work from the restart earned a penalty for Ulster, which Humphreys slotted with the final kick of the half.
Humphreys missed a chance to cut further into Clermont's lead six minutes into the second half after flankers Stephen Ferris and Julien Bonnaire had squared up to each other.
Ferris was later judged man of the match after producing another customary brilliant display in the white shirt.
Humphreys made no mistake from in front of the posts in the 51st minute to leave only two points between the teams.
The game became bogged down for the next 15 minutes with neither team creating a scoring opportunity.
Ulster coach Brian McLaughlin made a brave call 14 minutes from time by bringing off his two international props John Afoa and Court with Declan Fitzpatrick and Paddy McAllister introduced.
But it was another replacement, D'Arcy, who set up the crucial 70th-minute try as he countered from deep in his own half before producing a perfectly delayed pass to a charging Humphreys who held off Nataitaci to score.
The try-scorer added the conversion and suddenly Ulster were in control at five points ahead.
Replacement fly-half Brock James had already horribly missed a long-range penalty and the Australian fluffed another from in front of the posts five minutes from time with Skrela and Parra both off the field as Ulster held on for another famous win over French opposition at Ravenhill.
Ulster fly-half Ian Humphreys:
"Adam (D'Arcy) made a break from nothing and I was fortunate enough to be in the right place at the right time
"Tonight just proved how good our forwards are. I don't think we took a backward step anywhere.
Clermont second row Nathan Hines:
"Probably in a few days time we'll be happy with the bonus point.
"We started OK but they put us under enormous pressure at the scrum and that's how they kept in the game."
Ulster: S Danielli; A Trimble, D Cave, P Wallace, C Gilroy; I Humphreys, P Marshall; T Court, R Best, J Afoa; J Muller (capt), D Tuohy; S Ferris, C Henry, P Wannenburg
Replacements: A D'Arcy for Danielli 55, P McAllister for Court 67, D Fitzpatrick for Afoa 67, W Faloon for Ferris 76
Not Used: A Kyriacou, L Stevenson, I Porter, N Spence.
Clermont Auvergne: L Byrne; W Fofana, A Rougerie, R King, N Nataitaci; D Skrela, M Parra; L Faure, B Kayser, D Zirakashvili; N Hines, J Pierre; J Bonnaire, G Vosloo, E Vermeulen.
Replacements: JM Buttin for King 71, K Senio for Parra 69, C Ric for Faure 60, M Kotze for Zirakashvili 51, J White for Pierre 71, J Bardy for Vermeulen 64, B James for Skrela 64
Not Used: Paulo