SOMETIMES a single setback can teach you more than a string of successes.

That, at least, is the conclusion Adam Ashe believes he can take from being left out of the Glasgow squad for the PRO12 final last month.

After making his Test debut on last year's summer tour, the 21-year-old established himself this season as one of the most promising members of Vern Cotter's Scotland team. The same could be said of him at the Warriors, where his dynamic performances at No.8 seemed to have cemented his claim to be an almost automatic pick.

When it came to the final against Munster, however, Gregor Townsend thought differently, omitting Ashe from the squad altogether. It was not the first time that the coach had made a surprising team selection - and not the first time, either, that he was wholly vindicated, as his preferred back row of Rob Harley, Josh Strauss and Ryan Wilson played a vital role in the 31-13 victory.

In public, Townsend had explained when announcing his team that he had opted for maximum physicality, and omitted to criticise Ashe. In private, he told his No.8 that he thought he had fallen just short of top form over the preceding couple of games.

If there had indeed been a slight decline, it was one which many less-tutored eyes than Townsend's had failed to spot. But Ashe has now taken on board the lesson that, at the highest level of rugby, even a minor loss of form can be enough to make you lose your place.

"It was a tough time for me, obviously playing in the semi-final and then missing out for the final," he said earlier this week at the national squad's training camp in Font Romeu. "Gregor spoke to me and gave his reasons why. I've just got to use it as a learning experience: at Glasgow now you've got to be at the top of your game every time you pull the shirt on.

"Gregor obviously went for a different mix for that particular game, having a seven [Chris Fusaro] on the bench and Ryan in at openside. You just have to roll with it, I suppose. Gregor spoke to me and said he felt my form had dipped slightly in the couple of previous games. It didn't drop a lot, but just two or three per cent was enough for him to make the decision on that occasion.

"A lot of people said to me it was a harsh decision in some ways, but that's how it goes. Some people are going to miss out and be disappointed.

"You've got to put the team first in these situations. You want them to win and do well - and they did. We all played our part in getting us there."

It is a lesson Ashe hopes will help him keep his place in the squad for the Rugby World Cup when the numbers are cut from 46 to 31 at the start of September. He is one of nine listed as back-row players, although Harley, included with the locks, will also be among the competition.

And, no matter how much the week in France was about learning to work well together as a group, that competition will keep everyone on their toes as the countdown to the World Cup continues back at BT Murrayfield. "We're a team and we all get on pretty well, but at the end of the day you're competing with guys around you," Ashe added. "We're all pushing hard individually, but ultimately some people are going to make it and some aren't.

"It's certainly tough work," he continued when asked about the camp in the Pyrenees. "It's been enjoyable: we've had some tough times, but at the same time there's always been light at the end of the tunnel. For instance we climbed a hill, but then at the end of it we had a barbecue, which was good fun. It's a lot easier when everyone around you is putting the work in as well.

"He [Cotter] knows that every other country preparing for the World Cup will be doing the same kind of thing, so it's about going that extra yard to achieve gains in front of them. It's all for a purpose and everyone wants it."

That surprise omission by Glasgow has made Ashe want it all the more. But the Warriors' win in Belfast has also provided positive encouragement, by proving to a previously success-starved group of players that Scottish teams can emerge victorious on the big occasion.

"For us to win the PRO12 and Edinburgh to get to that European [Challenge Cup] final is fantastic. It does a lot for the country, gives everyone confidence and tells us that we're up there at club level so why can't we be up there at national level? Hopefully we can use that going into this campaign."