On that basis alone, Munster’s charter flight from Castres last Saturday night would have been a pretty muted affair. Win, and the sounds of Christmas carols make for a giddy journey home. By losing a frustrating game that was well within the team’s capacity to win, all that greets a protracted trip home is the sound of silence.

Munster now face a challenging period of three inter-provincial derbies in the clear knowledge that they butchered the opportunity to secure the vital away win that is a prerequisite for any side with designs on hosting a home Champions Cup quarter-final.

At all levels of rugby, players will face a specific opponent that is just horrible to play against. Munster’s first ever European Cup encounter on the road was against Castres back in 1995. A nasty undercurrent ran right through that game all of 23 years ago, and nothing has changed since.

The biggest fallout surrounded the alleged biting of Peter Clohessy by Ismaela Lassissi back in January 2002, for which the Castres player was originally suspended for a period of 12 months, before that decision was rescinded on appeal.

There has been bad blood between the sides ever since.

What was clear from last Saturday’s encounter was that every contact was laced with afters. Munster did their best not to react but it’s not easy when obvious indiscretions go unpunished by the officials. There was a time when, if the referee wasn’t going to address the issue, you had to sort it out yourself.

That approach was abandoned with the advent of professionalism. With up to 11 television cameras covering these games, players know that nothing goes unnoticed. Getting suspended not only lets the team down in the long run but also counts against you financially, missing out on match fees and win bonuses.

The issue I have with the way rugby is being officiated now is that, in many cases, the outcome of the act dictates the punishment. Circumstances meant that my first viewing of last Saturday’s match was with some friends, in a pub, on my way back from Dublin.

When Peter O’Mahony was poleaxed with a no-arms tackle, despite the fact that he wasn’t even in possession of the ball, the instant reaction from a group with a decent knowledge of the game was a red card.

On second viewing, the demand for that outcome grew stronger from an even wider audience. I suggested calm as a yellow card was the more likely consequence on the basis that O’Mahony landed on his back, and so it proved.

In a game where the tackle area is becoming ever more dangerous, the authorities need to address tackles of a reckless nature and not just pay lip service to it. Prior to the recent November internationals, World Rugby confirmed there would be increased sanctions for high or no-arms tackles only to see Owen Farrell go unpunished for two dangerous hits against South Africa and Australia. It made a mockery of that diktat.

In incidents such as the hit on O’Mahony and when it comes to adjudicating on aerial collisions, the colour of the card is shaped by the outcome.

Land on your neck or head — red card. Hit the ground with your back or shoulder — yellow. Thankfully, rugby hasn’t yet degenerated to the point where players feign injury to get an opponent sent off, with self-preservation the first priority. Hopefully, the game never degenerates to that point.

When Andrew Conway was attempting to pick up his kick ahead in the act of scoring a potential game-clinching try, he was compromised by a highly-dangerous sliding tackle by Castres No 10 Benjamin Urdapilleta.

Fortunately, his reckless act caused no damage. Had Urdapilleta’s studs caught Conway’s knee, stomach, or groin, forcing the flying winger to be carried off, there is every chance that Wayne Barnes might have awarded a penalty try. As things stood, it should have been at least a penalty.

I found it strange that, when reviewing the incident with the TMO to ascertain whether Conway had knocked on, the nature of that sliding tackle never even come up for discussion. Why not?

At least the citing of Rory Kockott to answer a gouging charge on Chris Clute is a recognition by the authorities that Barnes erred in not reviewing the incident at the time, while the citing of Marc-Antoine Rallier suggests that the nature of the tackle on O’Mahony might indeed have warranted an even higher sanction. That is a welcome development.

This latest defeat means Munster have left an additional five-point haul behind them in their two away games to date, three against Castres last weekend and two against Exeter at Sandy Park when the province drew a game they could also have won.

Even though they still have every opportunity to top Pool 2, the lack of points accumulated to date could see Munster finish up as fifth seed which would result in an away quarter-final.

Finishing as the fourth seed is still possible and would deliver a Thomond Park quarter-final date but to do that, Munster have to win next time out against Gloucester at Kingsholm. That will not be straightforward. Had Danny Cipriani not been sent off in their second-round clash in Limerick, the outcome of that match could have been entirely different.

The visitors still managed to score three tries after Cipriani’s dismissal and have shown steady improvement in the Gallagher Premiership under David Humphreys this season. That home defeat to Exeter last Friday night was a setback but they will be highly motivated to beat Munster.

Leinster showed against Bath at The Rec the importance of finding a way to win away from home when not at your best. It’s no coincidence either that the two biggest threats to Leinster’s aspirations for back-to-back wins to match the achievement of 2011 and 2012 are Saracens and Racing 92.

The capacity of those two to win away from home over the weekend — Saracens in Cardiff and Racing 92 at Welford Road — means that both are odds-on to host home quarter-finals. Racing’s four-try demolition of Leicester, with Simon Zebo once again prominent, highlights just how far the Tigers have fallen in recent times.

Leinster host Pool 1 table-toppers Toulouse at the RDS in January in what is undoubtedly the game of round five. Win that, and Leinster too will be hosting a home quarter-final.

Right now, even if Munster beat Gloucester, they will still have to back that up with victory over Exeter Chiefs in Limerick on the final day of action as the winner of the game between the Chiefs and Castres in round five will still be alive and kicking in the pool going into that final round.

As always, Munster like doing things the hard way.