Heineken Cup: For seven seasons in a row Irish rugby has had at least one quarter-finalist, sometimes two, in the Heineken European Cup, and in only one of those years did the provinces not have a home tie. But never in that time has their hold on the knockout stages looked so tenuous.

Munster's cool heads in a crisis at home to the Dragons under the Thomond Park floodlights, and a descending fog, on Saturday evening at least averted a potentially devastating triple whammy of defeats for the three European Cup contenders, but now all of them are compelled to look anxiously across the groups.

Both Munster and Leinster can still theoretically top their pools to ensure qualification and interest in the competition after January, but that now looks unlikely and in part requires favours beyond their control.

Realistically, Munster and Leinster look to be chasing the two quarter-final spots for best runners-up, and as things stand they're ranked third and fourth of the six second-placed teams.

Viewed in that light, Leicester's lucky 17-15 win away to the Ospreys, courtesy of a converted 85th-minute try by replacement Dan Hipkiss, was not good news, as it means Pool Three and Pool Two, involving Cardiff and Perpignan, could provide the best runners-up.

Thus, Munster and Leinster could yet be competing for one place between them, while the late denial of even a bonus point in their 18-10 defeat to Saracens has left Ulster third in Pool Four on nine points and facing elimination for the seventh season in a row even if they beat Biarritz at home and Treviso away.

In fact, two bonus-point wins and a 19-point haul might not be sufficient.

Munster are best placed of the three, if only just, on 13 points. Two bonus-point wins would ensure they top Pool One with 23 points provided they deny Sale a bonus point in the concluding pool game at Thomond Park, regardless of what Sale do at home to the Dragons in the penultimate pool fixtures on the second week of January.

But as this entails a trip to long-standing and bitter French rivals Castres on Friday, January 13th, and then a home tie with Sale the following week, it looks a tall order, all the more so after a failure to procure even one bonus point in the back-to-back wins over the Dragons.

When it was put to him that winning Pool One might now be out of Munster's reach, their captain Anthony Foley remarked: "You're assuming a lot. You're assuming Sale are going to go unbeaten. I wouldn't assume. You're talking about Gwent Dragons, the team who put us to the sword today, going up to Edgeley Park and rolling over. I don't see that. I think there's a lot of rugby left in this group."

Be that as it may, unless Munster obtain a bonus-point win at Castres on Friday, January 13th, then Sale could clinch the pool by doing so at home to the Dragons two days later.

Declan Kidney maintains that 21 points, achievable with two wins, is a probable qualifying threshold, and Leinster's former outhalf and video analyst Emmet Farrell, their appointed expert in this area, concurs.

Despite the controversy, regrets and heartache in their unlucky 30-28 defeat at Bourgoin, when victory would have left them best of the second-placed teams and might have seen them reach the last eight with one more win, Leinster's fourth bonus point leaves them only just behind Munster on 12.

Were Bourgoin to register a third home win against Bath on Friday the 13th, then Leinster victories at home to Glasgow the next day and away to Bath at the Rec the following weekend could well see them top Pool Five and ensure qualification.

Failing that, then Leinster still need to win both matches to have any chance of progressing, and were it to come with at least one more bonus point, that would give them 21 points. As they also have a healthy try tally, that would probably be enough for an away quarter-final as one of the two best runners-up. But that too will be against the odds now.