Ulster trailed for almost the whole of the first period, with Ian Keatley on form from the tee to kick three penalties, but Tommy Bowe broke through to score with the last play of the half to put Ulster in front.

And after Keatley and Jackson had exchanged second-half kicks, Iain Henderson's red card looked to have cost his side as Keith Earls went over in the corner with just four minutes remaining.

But replacement Paul Marshall charged over with the final play of the game to send a packed Kingspan Stadium into raptures, and Jackson's conversion from the sideline leaves the race for home GUINNESS PRO12 semi-finals wide open heading into the final weekend.

It was the visitors who made a fast start, but they lost flanker Tommy O'Donnell inside five minutes as he hobbled off with an injury.

The home defence held firm until Jackson was pinged for not rolling away and Keatley kicked the first points of the game.

The hosts responded well, and after good breaks from Jared Payne and Louis Ludik, Jackson's 9^th minute grubber-kick had to be touched down by Simon Zebo with Payne hot on his heels.

Ulster were creating all the chances, but it was Munster's Earls who came closest to opening the scoring when he was inches away from touching down, after the home side lost the ball in midfield and the winger chased down his own kick.

And Munster got the chance to double their lead on 31 minutes when Callum Black was guilty of not driving straight in the scrum, and Keatley obliged with a superb 40-metre kick from the sideline to make it 6-0.

The fly-half then made it three from three five minutes later, another kick from distance finding the target after Iain Henderson came in at the side, but Ulster finally got some points on the board on the stroke of half-time.

First Jackson's kick sailed through after Munster were penalised at scrum-time, and then after Rory Best claimed the restart, Henderson's brilliant offload released Bowe who broke a couple of tackles and finished brilliantly - Jackson adding the extras to turn the game on its head.

Ulster picked up where they left off, Darren Cave making a superb early charge up the field, before Jackson's penalty crept inside the post when Munster were pinged for obstruction.

But Keatley brought Munster back within a point on 54 minutes when Ulster were penalised in front of the posts, before his fifth kick of the afternoon moved the visitors back in front and edged him ahead of Ospreys' Dan Biggar as the GUINNESS PRO12's leading scorer.

Munster looked to have regained their earlier momentum with Ulster's scrum under pressure, but Bowe blew a fantastic chance to score again, attempting a no-look pass after scything through Munster's line.

And Ulster were punished again for naive defending when Marshall was pinged for a tackle on Earls, and Keatley landed his best kick of the afternoon from the right touchline to extend the lead on 69 minutes.

Jackson immediately responded however for the hosts with a penalty of his own with Munster offside, and with the difference just two points heading into the final ten minutes the game was set for a grandstand finish.

But Ulster's task got a whole lot harder when Henderson saw red on 73 minutes for a reckless hit on Ronan O'Mahony, and Earls looked to have made the result certain three minutes later after Felix Jones' pass put him into the corner.

Keatley missed his first attempt of the afternoon with the conversion, and that proved vital as the 14 Ulstermen went up the other end to score in the corner through Marshall, Jackson adding the extras from the sideline to level the contest.

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