In a feisty contest, the hosts played most of the contest with 14 men after Tom Court's dismissal but a try and 15 points from the boot of Jackson saw Ulster gain the point they needed to seal a top-four place.

Leinster had Rob Kearney and Rhys Ruddock sin-binned but saw Shane Jennings cross in the second half.

On top of that, 14 points from fly-half Ian Madigan and a further three more from substitute Jimmy Gopperth kept them four points above second-placed Glasgow Warriors in the RaboDirect PRO12 standings with just one game to go.

Leinster started ominously with the pack taking charge, and a huge scrum brought with it the first chance for Madigan to test his kicking skills on five minutes.

The Irish international made no mistake, and six minutes later he added another three-pointer from out wide on the left.

Madigan failed to make it three from three on 14 minutes, but Leinster's hopes were given a boost when Ulster prop Court, who is moving to London Irish next season, was shown a red card for a dangerous tackle on Devin Toner on 16 minutes.

The visitors tried to take advantage and thought they had scored moments later, but Jennings was deemed to have been held up on the line by a resilient Ulster defence.

Ulster's determination in defence was soon rewarded, after Leinster full-back Kearney had been sin-binned, when Jackson blocked Madigan's chip and crossed for the first try of the match on 24 minutes.

Jackson missed the subsequent conversion, but the hosts were back in the contest at 5-6 on the scoreboard and 14-14 on the pitch.

Another yellow card for Leinster, this time for Ruddock, gave the numerical advantage to the hosts and Jackson smashed over a penalty to give Ulster an 8-5.

But Madigan and Leinster had the last laugh of the half, with the visitors' penalty ensuring they went into half-time 9-8 to the good.

Madigan was proving hit and miss from the tee, missing his first two after the break, but a 53rd-minute success edged Leinster further ahead before Jackson responded with his own penalty five minutes later.

But almost straight from the restart Leinster grabbed their first try of the game through Jennings after some great play from Brian O'Driscoll - Madigan's extras made it 19-11.

Retiring captain Johann Muller was then given a rousing reception from the home fans after being replaced on the hour mark on what could have been his final appearance at Ravenhill, and it appeared to make the difference.

Jackson slotted three more penalties late on and - despite Leinster replacement Gopperth adding his own - it was enough to secure a top-four position for Ulster after picking up a losing bonus point.

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