Ulster lock Dan Tuohy scored twice at Ravenhill as the hosts ran in five tries to defeat Cardiff Blues 39-21.
A double from Tuohy, combined with tries by Jared Payne and Andrew Trimble, helped a clinical Ulster ascend the Pro12 table.
Cardiff Blues fought back with tries from Robin Copeland and Richard Smith, as well as the devastating boot of Leigh Halfpenny. The visitors were never less than competitive in an absorbing contest but Ulster, who led for most of the game, were worthy winners.
It was Ulster that made the more adventurous start, taking the Blues through several phases early on. It was a busy start to the game for the home side, but a knock-on two minutes in undid their hard work.
The Ravenhill men's scrummaging prowess was evident, with late call-up John Afoa particularly impressive.
One such shove earned a penalty on eight minutes, which Paddy Jackson successfully slotted. Lions' full-back Halfpenny restored parity three minutes later when he kicked a penalty though from close range.
The game ignited from an Ulster perspective on 17 minutes when some lovely handling involving Olding, Marshall, and Diack to unleash Tuohy in the corner. Jackson missed the resultant conversion to leave the score at 8-3.
The Welsh region responded with hard running and aggression, but the home defence was quite impressive.
Things got even better for the Irish side on 24 minutes when Jared Payne touched down after Jackson bravely spurned a gilt-edged three points and elected to run a penalty from five metres out. The Irish international once again missed the extras, however.
The Belfast outfit were now 13-3 in credit. Jackson redeemed himself on 28 minutes when he kicked another penalty following destructive work by the Ulster scrum. But Cardiff cleverly manoeuvred their way into the game, with fly-half Rhys Patchell orchestrating superbly.
The Welsh club's prospects were enhanced further on 34 minutes when number eight Copeland finished off some neat passing - Halfpenny uncharacteristically missing the conversion to make it 16-8.
The Lion stars made no mistake a fewminutes later however, when he reduced the gap to only five points. By half time, the visitors were certainly regaining their foothold in the match.
Ulster upped the tempo at the beginning of the second period, and the increased intensity paid dividends on 42 minutes when Marshall scored following an incisive jink by Olding. Jackson though neglected to add the extra points.
Copeland conceded another penalty three minutes later when he illegally prevented the release of the football - the big number eight yellow carded for his intervention. This time Jackson punished the Welshmen to make it 24-11.
The Blues responded resolutely, with Lions' skipper Sam Warburton leading the charge, and it was the Welsh club that struck next when wing Richard Smith dived over on 51 minutes. Halfpenny converted to leave the Blues only trailing by six points with Cardiff's increased physicality was beginning to grind the hosts down in this segment of the game.
But the unerringly accurate Pienaar settled Ulster's nerves on 55 minutes when he landed a sublime penalty from close to the half way line. Halfpenny responded as the match descended into a battle of place kickers, and Pienaar missed two difficult chances to augment his side's lead.
Andrew Trimble, excluded from the Ireland squad this week, managed to put some daylight between the teams when he finished a nice move on 67 minutes to earn Ulster a nine-point advantage as at last the forward supremacy of the home side began to tell and gaps began to emerge in the Blues' hitherto concrete defence.
Tuohy completed an unlikely brace on 80 minutes when he barged over in the corner.
The score may have flattered the hosts, but this was a decent victory nonetheless. The Welsh kingpins will be disappointed by their failure to follow up last week's heroics against mighty Toulon. For Ulster, this gritty home win, achieved through old-fashioned forward power and precision, keeps their title ambitions on track.
Tries: Tuohy 2, Payne, L.Marshall, Trimble
Pens: Jackson 3, Pienaar
For Cardiff Blues:
Tries: Copeland, Smith
Pens: Halfpenny 3
Yellow Card: Copeland
Ulster: 15 Stuart Olding, 14 Andrew Trimble, 13 Jared Payne, 12 Luke Marshall, 11 Tommy Bowe, 10 Paddy Jackson, 9 Ruan Pienaar, 8 Roger Wilson, 7 Chris Henry, 6 Robbie Diack, 5 Dan Tuohy, 4 Johann Muller (c), 3 John Afoa, 2 Rory Best, 1 Callum Black
Replacements: 16 Rob Herring, 17 Tom Court, 18 Ricky Lutton, 19 Lewis Stevenson, 20 Mike McComish, 21 Paul Marshall, 22 Darren Cave, 23 Michael Allen
Cardiff Blues: 15 Leigh Halfpenny, 14 Richard Smith, 13 Cory Allen, 12 Dafydd Hewitt, 11 Harry Robinson, 10 Rhys Patchell, 9 Lloyd Williams, 8 Robin Copeland, 7 Sam Warburton, 6 Josh Navidi, 5 Filo Paulo, 4 Bradley Davies, 3 Scott Andrews, 2 Marc Breeze, 1 Gethin Jenkins (c).
Replacements: 16 Kristian Dacey, 17 Sam Hobbs, 18 Taufa'ao Filise, 19 Lou Reed, 20 Rory Watts-Jones, 21 Lewis Jones, 22 Gareth Davies, 23 Chris Czekaj
Referee: Giuseppe Vivarin (FIR)
Assistant Referees: Gary Conway, Eanna O'Dowd (both IRFU)
TMO: Peter Ferguson (IRFU)
by Rory McGimpsey