JACKSON COLUMN: Have Leinster turned corner in title tilt?

Ulster's arrival in Dublin raised the possibility that a weekend which began with the champions eight points adrift would end with the gap widening to twelve. Ruan Pienaar's early penalties and the rare sight of Jamie Heaslip being forced to leave his post did nothing to dispel the worst-case scenario.

Despite the disruption, Leinster won as they invariably do in the PRO12 at the RDS, Ian Madigan steering his team home to a 17th successive win there since the Ospreys managed a draw way back in September 2013.

Heaslip, a monumental figure with a matching record of 270-plus appearances for Leinster, Ireland and the Lions, had not been forced out of action since a European Cup tie four years earlier. How typical of Leinster's response to his loss that their redesigned back row should feature a man-of-the-match effort from Heaslip's replacement, Jack Conan.

In only his seventh PRO12 start, the 22-year-old stepped into the breach with a winning contribution to a back row that had already been hit by the pre-match withdrawal of flanker Shane Jennings. Ulster finished up losing for the third time in four PRO12 matches.

Leinster had the added satisfaction of sending their opponents home empty-handed when a losing bonus point could conceivably have been enough to keep them in the top four a fraction above the victors. Elsewhere, the news just kept getting better and better for Leinster.

Munster had gone down to Connacht on New Year's Day after a journey to Galway as pointless for them as Ulster's in Dublin. By then the Warriors discovered that, for all their perennial consistency in the Guinness PRO12, nothing could guarantee them immunity from the shortest trip of the season turning into the most punishing one.

The Warriors found Edinburgh and a 15,000-plus crowd at Murrayfield too hot to handle. Two Tim Visser tries, his first since mid-October, gave the hosts the foundation for a win hefty enough to obliterate the previous week's ten-point deficit at Scotstoun and regain the 1872 Cup.

In breaking Glasgow's six-year monopoly of the domestic trophy, Edinburgh signaled their intention to climb into the top seven and ensure more than one Scottish team qualifies for the European Champions' Cup.

Munster, Ulster and the Warriors having failed to muscle a solitary point between them, the Ospreys also fell foul of local rivals. The Scarlets, confident of evening up the score after running their neighbours close in Swansea the previous week, duly did so. Not for the first time, Alun-Wyn Jones and the league leaders found the twelve-mile trip to Llanelli too hard to negotiate.

A 22-10 home win added to the feel-good factor swirling around the Parc y Scarlets which began with Scarlets' Test forwards Jake Ball and Rhodri Jones signing national dual contracts, thereby securing their future in Wales.

Now, more than ever, the Scarlets need to engineer a winning streak if they are to achieve their lofty pre-season objective of a top-four finish. Scott Williams, their captain and try-scorer, considers it 'definitely possible' but only if they strike a level of consistency.

Just once in the PRO12 this season have the Scarlets managed to win successive matches, against Zebre and the Warriors in November. Friday's trip to Glasgow offers them the chance of completing the double albeit at the most challenging of venues.

The Warriors have reeled off 14 straight PRO12 wins at Scotstoun since the Dragons won there 14 months ago. At the same time, Connacht put their own imposing home record on the line against Edinburgh.

Galway, where Pat Lam's team have not lost all season, will provide a severe test of Edinburgh's revival. Leinster, Munster, La Rochelle and Bayonne are among those who have sampled the experience out west and suffered accordingly.

Leinster, the only one of the top five to avoid defeat last weekend when just about every result went their way, will hope to narrow the gap against the Blues in Cardiff.

While the holders are resigned to being without Heaslip following his shoulder injury against Ulster, they expect to be reinforced by the return of four members of their lengthy casualty list.

Rob Kearney, Eoin Reddan, Marty Moore and Dominic Ryan are all available again. Other long-term absentees, Sean O'Brien and Cian Healy, will take longer. Not for nothing, therefore, does forwards' coach Leo Cullen argue that Leinster are 'entering a period which very much defines our season.'

Ulster, too, have been hit by a heavy injury toll with head coach Neil Doak putting the number as high as twelve. Almost half of them - Andrew Trimble, Iain Henderson, Jared Payne, Chris Henry and Nick Williams - are still some way from being fit to return.

This weekend takes Ulster to Treviso, to the Stadio Communale di Monigo where a season's best 5,000 saw the home team complete a festive double over Zebre and move off the bottom at the expense of their Italian rivals.

When they were last there, at the height of the Six Nations last February, Ulster scraped through 14-12 thanks to converted tries from Darren Cave and Robbie Diack. At the same venue two months ago Leinster scored four tries and conceded four and ended up escaping with a draw.

The Guinness PRO12 and how they stood after twelve rounds last season:

1 Munster 43 pts
2 Leinster 40 pts
3 Ospreys 39 pts
4 Ulster 37 pts
5* Warriors 33 pts
6 Dragons 24 pts
7 Scarlets 23 pts
• Warriors had played ten matches to everyone else's twelve due to the postponement of home fixtures against Edinburgh and Benetton Treviso.

How they finished:

1 Leinster 82 pts
2 Warriors 79 pts
3 Munster 74 pts
4 Ulster 70 pts

After twelve rounds this season:

1 Ospreys 40 pts
2 Warriors 39 pts
3 Munster 37 pts
4 Leinster 36 pts
5 Ulster 35 pts
6 Connacht 32 pts
7 Scarlets 28 pts

How they will finish is anyone's guess…

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