There is a real sense of this being a crucial time for Scotland's professional players as Glasgow and Edinburgh prepare to meet Munster and Connacht respectively on Ireland's wild west coast tonight.

No fewer than 12 of those involved in the national team's excruciating defeat by Tonga last weekend have been pressed immediately back into action and the state of the rugby nation is starting to bring about some changes of thinking, it seems.

"In the past we might not have brought the Scotland players straight back in and maybe given them the weekend off after the Tests, but it's vital we build on the momentum from the Ospreys match and have picked a strong side with the aim of doing just that," said Michael Bradley, Edinburgh's coach.

Maybe so, yet while Glasgow Warriors can hardly be described as looking to build on momentum after they failed to register a point last week in losing to Leinster on their return to action after a three week lay-off, all of their men who started the Test have also been recalled.

The reality is that with both teams having been effectively knocked out of the Heineken Cup just before an autumn Test series in which Scotland lost all three matches, there is an increased emphasis on the RaboDirect PRO12 as they look to turn things around.

That is perhaps all the more so the case with the first of the Inter-City matches between the Scottish sides only three weeks away, following two more rounds of European action in which both Glasgow and Edinburgh will try to stimulate some hope of being involved in the Amlin Challenge Cup quarter-finals.

Rather more than the 1872 Challenge Cup and a bit of pride may be at stake this year, but this weekend's matches will decide whether Glasgow, in third place before today's games, will have a bit of a cushion or whether Edinburgh will be able to overhaul them in the derbies.

Before that, though, there is a chance for Glasgow to learn from Edinburgh's recent experience in Munster in the Heineken Cup as Gregor Townsend, their head coach, acknowledged. His observation about the way Munster have been seeking to change their game echoed Bradley's description of the Irish side.

When reminded of that Townsend said: "I remember that game. They moved from side to side early on then went back to their strength and it's a potent mix when you've got that history and the ability to play that way, but also to move a team around in defence."

That Fetu'u Vainikolo may be deemed surplus to Connacht's requirements against Edinburgh a week after he put Andy Robinson out of a job seems telling, not least when set alongside the inclusion of another man who gave the former Scotland head coach some dilemmas to deal with over the years.

Dan Parks' inclusion for tonight's game, allied to the absence of the Vainikolo, whose rocket-fuelled run produced Tonga's match- winning try at Pittodrie last weekend, offers a pretty clear indicator of the home team's likely approach in Galway.

Parks' Connacht debut came in a crushing home win over Leinster two months ago and he has since helped them to wins over Zebre in the Heineken Cup and Treviso in the league. The Italians may have replaced the Scottish teams in being seen as the weak link in the PRO12 mix but, as Bradley acknowledged yesterday, matches against Edinburgh and Glasgow Warriors are still looked upon even by the weaker teams in the competition as matches they ought to win.

"Connacht target the arrival of the visiting Scottish sides because they feel they've an excellent chance of winning those games," he said. "We've talked about that a lot at training this week as something we must change."

No-one knows the Connacht mindset better than Bradley, who spent nine years with the province, but even his experience of what to expect did not protect Edinburgh when they went to Galway last year.

Increasingly, too, Connacht are entitled to see themselves as more than the development side they had to be for so many years under Bradley. Parks and Vainikolo are among a handful of experienced imports recruited to help the home-grown talent and it is paying dividends. Consequently, they, like their nearest neighbours Munster, are in a very different position to the Scottish opponents they play host to this evening.

Connacht may not have quite managed to replicate last season's achievement in beating Harlequins in their first Heineken Cup campaign, but their eight- point defeat this time around, allied to their defeat of Zebre, means they are preparing for back-to-back matches with former finalists Biarritz over the next two weekends, which are likely to decide whether they can book a place in the last eight of the Amlin Challenge Cup. As they re-set their sights, Connacht will continue going about their business in their usual pragmatic, rumbustious way, recognising, as they do, their strengths and weaknesses and playing accordingly.

That is why Eric Elwood, the former Ireland stand-off who is their coach, employed Parks. However, the prospect of involvement in those matches should only add an extra edge to their efforts to impress today, just as it offers – for all that there have been criticisms of their national side – a reminder of the relative health of the Irish game at provincial and national level when compared to Scotland's.