Henry Pyrgos will break the nine-year domination of Scotland's scrum-half berth by Mike Blair, Chris Cusiter and Rory Lawson after being named as one of five changes to the XV for Saturday's Test with Tonga, as the balance of power in the national squad swings to the west.

Al Kellock, the Glasgow Warriors captain, and two of the club's former players, Max Evans and Scott Lawson, were also recalled along with Al Strokosch, who hails from East Kilbride. Uncapped duo Tom Heathcote, the 20-year-old Inverness-born Bath stand-off, and Grant Gilchrist, the Edinburgh lock who hails from Alloa, are poised to make their Test debuts after being named on the bench.

Blair, the man dropped for Pyrgos, is left out of the squad altogether, as are Ross Ford and Jim Hamilton, both of whom played for Edinburgh under Andy Robinson, the Scotland coach. However they are respectively replaced by long-standing squad members in Lawson and World Cup captain Kellock.

Pyrgos, however, admitted even he has been surprised by the speed with which he has come through the ranks. As well as belated recognition of his club's superiority of the domestic scene, the selection of the Glasgow scrum-half to end the hegemony of a trio of former Scotland captains, reflects a remarkable change of fortune on a personal level.

When this season began, Pyrgos looked as if he might have been battling to see much action at club level with Cusiter firmly established as the first-choice scrum-half and Niko Matawalu, the Fiji internationalist, having been recruited.

"This was the last thing on my mind at the start of the season," Pyrgos admitted. "I was just looking forward to a new coach at Glasgow and to working hard and doing well. I was playing quite well and it was great even to get in the squad, so to be involved in the New Zealand game was amazing. I loved it. Then to get on against South Africa and get a start against Tonga . . . it is amazing that has all come so quickly.

"I am just trying to improve every week and it is amazing I have this opportunity to go out there and try to play well. It is nice to know that I have done well but I can still get a lot better. I now have to kick on, working hard and learning from the guys around me. I can pick up tips from them and with all the other experienced guys around me learn and keep trying to get better."