The last unbeaten record in the PRO14 fell at the RDS as Ulster came up short, and then short again, against Leinster.
Having led 9-5 at half-time, their second-half efforts would be rewarded with only a sole John Cooney penalty as the third quarter again proved to be something of a problem.
Once the game was well and truly gone in the final few minutes, Ulster could not rally themselves to bag a losing bonus-point, the 5-0 swing in match-points allowing the three-in-a-row champions to seize the advantage in Conference A.
While the sides will meet again in Belfast this season, with Ulster now just five points ahead in the table, and Leinster in possession of two games in hand, the northern province’s margin for error has now evaporated.
So much of the week’s narrative had centred upon how Leinster would respond to the end of their long winning run in the PRO14 and that ultimate rarity - a loss at their RDS home.
If Leo Cullen’s men were intent to make an early statement, however, they would need to do so without the ball.
Ulster monopolised possession in the early stages with the league champions living off scraps and the odd knock-on.
The physical battle on the gainline was certainly worthy of such a consequential inter-pro but Ulster’s lead through a John Cooney penalty was well deserved.
That three-pointer wasn’t quite first blood though, that honour going to Marty Moore who had to depart with a cut to the head caused by the rampaging run of his team-mate Marcell Coetzee.
Ulster’s tight-head would not return and it was his replacement, Tom O’Toole, who was pinged at the scrum to give Johnny Sexton a chance to level things up at the end of the first quarter. The Ireland skipper, though, skewed his effort comfortably wide of the near upright.
Having failed to trouble the scoreboard with that effort, when Marcell Coetzee was whistled for a high tackle on Andrew Porter, Leinster would this time go for the corner.
They would get their reward when, after a lengthy Ulster resistance on their own line, Jamison Gibson Park spun the ball to Dave Kearney and the wing somehow squeezed into the corner before being tackled into touch.
Coetzee’s second high tackle in quick succession would see him sin-binned but, down a man, Ulster would take a lead just minutes before half-time when having worked out a few early line-out kinks, they earned another shot at the posts that Cooney again knocked over.
And, just as the soon-to-depart Springbok was set to return to the field, Cooney made it three from three after more excellent breakdown work brought another blast of Andrew Brace’s whistle.
Six-points to the good at the turn, and 6-0 to the good through the sin-binning period, Ulster will have sensed they had it within themselves to strike a decisive blow in the race for Conference A’s sole final place.
But there were only three minutes elapsed since the restart when, having piggy-backed penalties, the visitors would face a five metre lineout and couldn’t prevent the prolific Sean Cronin from barging over from the maul.
Just three points to the good but with momentum certainly in their favour, Leinster pressed ahead as Ulster’s discipline eroded away. Jordan Larmour would have gone over if not for the last-ditch intervention of James Hume but Leo Cullen’s men would bag the crucial next try when Robbie Henshaw broke through a pair of tackles.
Key interventions at key moments - a Coetzee breakdown turnover and Kieran Treadwell line-out steals - kept Ulster in touch as the hour mark neared but going into the final quarter there felt only one winner.
With the table so finely poised, the result was not the only thing looming large with the distribution of match-points feeling like it carried out-sized significance.
When replacement hooker James Tracy went off his feet at the breakdown, Cooney would line up his fourth penalty of the night and his fourth successful effort not only brought Ulster back within a score to set up a grandstand final ten minutes but also dragged them back within losing bonus-point range.
Tracy’s 75th minute score, therefore, felt doubly impactful, all but securing the victory for one but also shifting the points spread from 4-1 to 5-0. Ross Byrne’s conversion meant it would require a late try for Ulster to take anything back home and that loomed large when, with the clock red, they went through near 20 phases and won a kickable penalty. Under the circumstances, they had no choice but to go for the corner.
As close to a try as they’d come all evening, again the phases counter ticked up ticked up, with the clock nearing 84 minutes but Byrne’s intercept ended the challenge.
Quite how important that passage of play, and this result, will be in the this season's story will become clear only over the next two months.
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