Rob Herring and man-of-the-match Stuart McCloskey went over for first-half scores for Ulster - who have still not lost in the GUINNESS PRO12 at home since May of last year.

And while Sam Davies slotted two penalties for the visitors, Wiehahn Herbst went over soon after the interval to effectively seal victory for the home side.

In an evenly-matched final quarter, Ulster looked like they had blown their chance of a fourth try and a bonus point but a fine surge by Craig Gilroy set up Marshall to go over in the left corner.

Unsurprisingly considering their fine home record, it was Ulster who started the brightest and they had their first try of the season inside five minutes.

The initial break came from Willie Faloon, in his first competitive game back with province, and when the ball was recycled Paul Marshall fed Herring and the hooker powered over from close range for his first try since being given the captaincy.

McCloskey took on the kicking duties in the absence of both Ruan Pienaar and Paddy Jackson but he snatched at his first relatively simple conversion attempt and pushed it wide.

But he soon made amends for that miss, obstruction by Jonathan Spratt gave Ulster a penalty from right in front, and this time he slotted over for an 8-0 lead.

Ospreys' first chance for points came from bang in front and former junior world player of the year Davies slotted over via the right-hand post to reduce the lead to 8-3.

But Ulster were starting to click into gear and Andrew Trimble, in his 189th game for his province, showed Joe Schmidt and Ireland what they are missing with a searing break from his own half. And when the ball was spread right it was McCloskey who powered his way over the line, a huge hand-off on Spratt allowing him to stride clear and hold off two would-be tacklers to score.

The centre was starting to enjoy himself and he added the touchline conversion as well for a 15-6 half-time lead - Davies pulling back one penalty just before the interval for the visitors.

After the interval the Ospreys' front row showed some dominance in winning a penalty against the head but Davies missed the kickable penalty and the lead stayed at nine points.

Another McCloskey break soon had the hosts back on the front foot however and when the Ospreys impinged at the breakdown the centre took the points on offer by slotting a penalty from bang in front.

The next time they found themselves in Ospreys territory they went to the corner however, and while the driving maul from the lineout fell short, Herbst was on hand to barge over in the right corner with help from Faloon.

McCloskey's conversion was off target but with a 23-6 advantage and less than 53 minutes played, the Kingspan Stadium faithful were already thinking about a bonus point.

But in truth the final quarter of the game was a scrappy affair, Osprey Joe Bearman given a yellow card for a dangerous clearout after the hour mark.

But the home side could not make their man advantage count and in the end a try bonus point looked to have eluded them before Marshall went over with virtually the last play of the game.

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