The Champions Cup has become an inhospitable environment for Leinster, Munster, Ulster and latterly, Connacht. It's a little over four years since Ireland's last success in the tournament when Joe Schmidt's Leinster beat provincial siblings Ulster at Twickenham.

European rugby’s landscape has changed considerably in that period and not just on the pitch. The competition has been rebranded, the qualification process changed and the goalposts nudged in the direction of the financial behemoths in France and England to accommodate the whims of those that preside over some of the marquee clubs.

Last season all three provinces – Connacht were back in the Challenge Cup – failed to qualify for the knockout stages of the tournament, a sobering low point when weighed against a proud record of six European titles. The hiatus since the last victory now enters a fifth campaign that gets under way this weekend.

Connacht are back in the hopper following their superb Guinness Pro12 triumph last season. All four Irish provinces face French opposition, Leinster host Castres Olympique, Connacht welcome Toulouse to the Sportsground while Munster travel to Paris and Ulster to Bordeaux.

Triumphed

A good start is half the battle, or so the saying goes, but is it really as a barometer of potential success for the Irish provinces in a given tournament?

For the purposes of the graphics below the case study pertains to the last 10 seasons of the Champions Cup and its previous incarnation. It specifically focuses on how the Irish sides fared in the opening two-match block to establish what if any patterns emerge.

In broad brushstrokes, Leinster have won 70 per cent of the accumulated round one and two matches during that 10-season period, prevailing in 14 of 20 matches with one drawn. Munster (65 per cent) have won 13, while Ulster (45 per cent) have triumphed on nine occasions.

Munster traditionally prefer to play away from home in round one and that is undoubtedly a factor in losing six of seven fixtures – the only victory on the road in that time was against the Sale Sharks, 27-26, in the 2014-2015 campaign – while winning all three home matches.

Conversely Leinster generally opt to play their opening European match at the RDS but during the timeframe specified, they have suffered quite a poor return losing three of seven matches; Bath (22-19), London Irish (12-9) and Wasps (33-6) have left Dublin with the points.

Perversely

Indeed perversely Leinster never lost away from home in that time in round one beating Edinburgh (27-16) and the Ospreys (19-9) while drawing 16-16 with Montpellier, whom they meet in round two this season.

Ulster also tend to plump for a home game on the opening weekend of Europe, winning six of eight at Ravenhill/ Kingspan stadium, their two home defeats against Gloucester (32-14) and Stade Francais (26-10). They have won one and lost the other match on the road.

In the round two fixtures, Munster have won a superb nine from 10 matches, all seven at home and two away, their sole defeat, against Stade Francais (27-7) last season, ending a remarkable sequence of wins.

Rassie Erasmus' charges will be sticking to a tried and trusted formula travelling to Racing 92 next Sunday and then hosting the Glasgow Warriors the following Saturday.

Leinster have won five of seven away matches in round two, a fine achievement, and eight of 10 in all; the two away losses were against Toulouse (33-6) and Bath (19-16). During the same period Ulster have managed just two wins from 10, Glasgow and Montpellier, both away.

Hat-trick of defeats

For the first eight years in the sequence Ulster played the round two match away and this season will be hoping to avoid a hat-trick of home defeats having been beaten by Saracens two seasons ago and Toulon last year. The Exeter Chiefs are the visitors on Saturday week.

Connacht have appeared in only three Champions Cups, losing four from six matches in the opening brace of fixtures, their two wins coincidentally against the same team Zebre.

So are there any positive auguries from when the Irish provinces conquered Europe in times past? In 1999 when Ulster were kingpins, they didn’t win either of the first two games, drawing with Edinburgh at home and losing in Toulouse.

However, there are parallels fixtures wise from Irish rugby’s multiple European winners. In 2006 and 2008, the years in which Munster ruled Europe, they went down away from home in the opening game of those tournaments, losing to English clubs Sale Sharks (27-13) and Wasps (24-23) but then the following weekend beat French sides, Castres (42-16) and Clermont Auvergne (36-13) at Thomond Park.

During Leinster’s three triumphs, they never lost a match in the opening two rounds, winning five and managing that 16-16 draw with Montpellier.

And just in case there is a feeling abroad that Irish provinces are on to a good thing if they can manage to win their opening two fixtures in a European campaign, Munster (2014-2015) and Leinster twice (2012-2013 and 2013-2014) managed just that feat . . . and then failed to qualify for the knockout stages.