12 Dec, 14:42
Prop Cian Healy is expected to miss the start of the 2014 RBS 6 Nations after undergoing surgery on his injured ankle on Wednesday.
In a defence-dominated first half at Ravenhill, it was a penalty apiece from Niall O'Connor and Duncan Weir until the returning Jared Payne released Michael Allen for a 38th minute try.
The young winger's first league score gave Ulster an 8-3 interval lead, punishing the Scots who were down to 14 men after a yellow card for Tommy Seymour.
Five minutes after the restart, Craig Gilroy swooped on a Weir pass to run in an intercept try from deep and O'Connor's conversion stretched the margin to 12 points.
Seymour showed his excellent finishing skills to run in a converted try that made Ulster sweat late on, although an O'Connor penalty restored the match-winning cushion as Mark Anscombe's charges passed their first test of the new season.
The strong tackling of man-of-the-match Robbie Diack and debutant Nick Williams was an early feature for Ulster, whose defence stood up to an initial spurt from Glasgow.
After a tightly-contested opening spell, the hosts found some rhythm with Michael Heaney's swift distribution inviting Williams and company to crash through.
With Paddy Jackson picking up a knock, his replacement O'Connor's first involvement saw him slot an 11th minute penalty for the lead.
This stop-start game began to open up at the midpoint of the half, Payne's half-break out of the 22 raising the decibel level and Weir's fine kicking keeping Glasgow on the move.
Good driving from the Warriors pack earned them a shot at the posts, with Williams conceding a close-in penalty that Weir comfortably converted.
Influential number 8 Williams almost redeemed himself, powering up close to the Glasgow try-line only to lose the ball in contact after O'Connor's well-angled kick to touch.
O'Connor should have made it 6-3 but knocked a penalty off the right hand post, amid a better period for Anscombe's experimental side.
The in-form Diack and new flanker Sean Doyle got on the ball more as the half hour approached, Ulster's improving continuity earning them a third kickable penalty that O'Connor slid just wide.
The out-half's precise kicking out of hand got the Ulstermen into scoring range soon after, Rob Herring piloting a well-orchestrated lineout maul that ended with a penalty and Seymour being dispatched to the sin-bin.
Ulster wisely used their dominant scrum to launch a late salvo. Lewis Stevenson got over the gain-line and then Payne's switch of angle and superb skip pass put Allen over unopposed in the left corner.
O'Connor was unable to convert the try from wide out and Weir was narrowly wide with an injury-time drop goal effort, as Ulster went in at the break with a five-point buffer.
Glasgow built up a head of steam early in the second half, profiting from a couple of powerful bursts from Graeme Morrison and Weir.
However, just when the visitors looked poised to strike in the Ulster 22, Gilroy shot up out of the line to intercept a pass from Weir and dart away to score a crucial second try.
O'Connor converted from in front of the posts, yet Glasgow remained dangerous and the additions of John Barclay, Dougie Hall and Moray Low strengthened their pack considerably.
Chris Farrell and Allen continued to show well in the youthful Ulster back-line, the former using his big frame to good effect in both defence and attack.
Glasgow replacement Ruaridh Jackson missed a penalty as the game entered the final quarter, by which stage Tom Court had come on to win his 100th Ulster cap.
But the game was right back in the melting pot when Gregor Townsend's outfit struck for a deserved try with 12 minutes remaining. Jackson's floated pass invited Seymour to cut past Luke Marshall and his clever footwork saw him beat the covering Gilroy to score in the right corner.
Jackson added the extras to make it a five-point game and ensure a nervy finish for the men in white, who were being caught too narrow at times.
A wind-backed O'Connor missed a difficult penalty chance, but Ulster lifted the tempo again in the dying minutes. Allen threatened from a cross-field kick and replacement scrum half Paul Marshall probed from a trademark quick tap.
Luke Marshall almost wrestled free of a defender close to the Warriors' posts, before a last-minute penalty from O'Connor clinched it for Ulster and denied Glasgow a losing bonus point.
|Ulster Rugby Score Card|
|Glasgow Warriors Score Card|