IF THERE is one thing more frustrating than complete omission from your team for a big match, it is surely being named as 24th man.

You travel with the squad, you can even warm up on the pitch with the squad - but you take no part in the actual action. You are a spare part, there only to be called on if someone is injured in the build-up.

That was the situation in which Henry Pyrgos found himself at the 2014 PRO12 final. A year on, the Glasgow Warriors scrum-half has gone from spare part to vital cog: not only a key playmaker, but also an increasingly influential leader both on and off the field. A major factor in that rapid growth in stature has been the self-discipline with which he has dealt with disappointments such as last year's, and which was evident when, earlier this week, he explained how he coped with being left out of that defeat by Leinster.

"It was disappointing, but ultimately I understood," said Pyrgos, who appears sure this time to be in Gregor Townsend's squad for tomorrow's final against Munster. "We had been playing well as a team, beating good teams home and away, and we started with Cus [Chris Cusiter].

"I knew that it wasn't about individuals, it's about the collective, and it was a shame we fell short. Leinster played really well in the final and it wasn't to be, but hopefully this year we have the squad to go one better.

"I feel like I've always had a big part to play here, even last season. We've used about 50 players this season. Over a long season you need to have a good squad to do well in this competition. It's great to be involved in the final - it's going to be a massive test and we're desperate to win.

"Getting to play in these big games is what you want. I've been fortunate enough to play in a few - international games too, which gives a lot of confidence. And not just semi-finals and finals, big away games at the likes of Leinster and Munster as well. Going to these places and picking up wins in the last few years has brought the squad on. Confidence is a massive thing in sport. In the first few years I was here we struggled to win away, but recently we've put some big teams away. It gives us huge belief."

That self-belief has no doubt been enhanced by those big wins, but it is also founded on the fact that Glasgow have been steadily and consistently improving for some time, in run-of-the-mill matches as much as in crunch clashes. And Pyrgos' individual progress has matched that collective improvement, even if the scrum-half himself prefers to give others the credit.

"Every year since I've been here" - he joined in the summer of 2010 - "we've got better," the 25-year-old continued. "You have to. If you stand still in this competition you're going to struggle.

"In Europe we fell a bit short this year; it's tough, but I know next year that will be a big target for us to get out of the group. We're building each year. Hopefully this weekend we can take another step, I believe we can.

"I feel like I'm playing pretty well at the moment. If the forwards play well it makes my job a little easier. I feel like I've had a good season and it's just a case of doing my job well. I've got a lot of talented playmakers around me and it's just about facilitating them, getting them the ball and putting them in positions where they can do their stuff. We've got some wonderful players, and hopefully at the weekend we can get the upper hand on them and I can help us towards a big victory."

Such hopes were dashed by Leinster last year but, as he watched on from his unique vantage point, Pyrgos was convinced the 34-12 defeat said more about the Irish province's prowess than his own team's shortcomings. "Looking from both the inside and outside last year, I don't think it was the case that the occasion got to us. I think Leinster just played well. They're a great side who have won the last two league titles.

"This weekend we know it's going to be as tough against Munster. They're a hugely physical side. We're going to have to break them down, and when we get opportunities we'll have to take them."

As Pyrgos went on to explain, that last remark applies not only to individual moments within the game, but to the contest as a whole. Games of this magnitude do not come around with any frequency in most players' careers, so he and his team-mates know they will need to make the most of this one.

"I won a few things at school, but professionally I've never won anything. We've been talking about this in the squad: when you look back on your career you want to grasp these opportunities when they come along. How many finals are you going to get?"