Nick Williams' late try clinched a 10-3 victory for Ulster over Connacht in Saturday's Boxing Day derby in the PRO12.
In a frustrating first period, Paddy Jackson scored the only points of the half as the Northern Irish province moved 3-0 ahead at the break.
Both defences continued to hold firm in the second 40 minutes but AJ MacGinty's penalty levelled matters.
A draw seemed on the cards until three minutes from time when Ulster launched a decisive attack and Williams crossed the whitewash for the winning score.
The Galway-based outfit have enjoyed an outstanding season so far, but injuries have hampered their progress over recent weeks.
However, they still had an opportunity to regain top spot in the league following the Scarlets' narrow loss to the Ospreys earlier in the day.
Pat Lam's men duly opened with intent and some excellent handling – a trait prevalent under the former Samoa international – gave them chances to exert pressure on the opposition defence.
Ulster remained firm for the most part, despite having to withstand a succession of phases close to the line. Les Kiss' side took advantage of that profligacy and Jackson's penalty – two minutes after Craig Ronaldson had missed a three-point attempt for the hosts – gave the visitors a 3-0 lead at the interval.
The second period started in much the same fashion as the first, with the home team attempting to find ways of breaching a resilient rearguard.
Once again, Ulster were steadfast without the ball and attempted to pounce when the few opportunities presented themselves.
They almost scored as Rory Scholes, who had displayed his threat earlier in the match, broke through off a first-phase move.
When the ball was shifted wide to Andrew Trimble a try looked inevitable, but the wing failed to hold onto the final pass.
It proved costly as Luke Marshall was yellow carded minutes later for a cynical trip and American international MacGinty equalised from the tee.
Apart from that penalty by the replacement stand-off, Ulster managed the sin-bin period impressively and finished the game the stronger.
Intelligent kicking from Paul Marshall and Jackson put Connacht on the back foot and, following a scrum 10 metres out, Luke Marshall burst to within inches of the line.
The hosts just about prevented the centre from touching down, but Williams was on hand to power over from close range and snatch the win for the visitors.
Yellow Card: L Marshall
Connacht: 15 Tiernan O'Halloran, 14 Niyi Adeolokun, 13 Bundee Aki, 12 Craig Ronaldson, 11 Matt Healy, 10 Jack Carty, 9 Kieran Marmion, 8 Eoghan Masterson, 7 James Connolly, 6 John Muldoon (c), 5 Aly Muldowney, 4 Ultan Dillane, 3 Nathan White, 2 Dave Heffernan, 1 Finlay Bealham
Replacements: 16 Shane Delahunt, 17 Ronan Loughney, 18 Rodney Ah You, 19 Andrew Browne, 20 Sean O'Brien, 21 Ian Porter, 22 AJ MacGinty, 23 Rory Parata
Ulster: 15 Louis Ludik, 14 Andrew Trimble, 13 Luke Marshall, 12 Stuart McCloskey, 11 Rory Scholes, 10 Paddy Jackson, 9 Ruan Pienaar, 8 Nick Williams. 7 Sean Reidy, 6 Robbie Diack, 5 Franco van der Merwe, 4 Alan O'Connor, 3 Wiehahn Herbst, 2 Rob Herring (c), 1 Andy Warwick
Replacements: 16 John Andrew, 17 Callum Black, 18 Ricky Lutton, 19 Stephen Mulholland, 20 Roger Wilson, 21 Paul Marshall, 22 Ian Humphreys, 23 Sammy Arnold
Referee: Peter Ferguson (Ireland)
Assistant Referees: Dudley Phillips (Ireland), Eddie Hogan-O’Connell (Ireland)
TMO: Jude Quins (Ireland)