Barclay made his international debut against the All Blacks in this year's Rugby World Cup the day before his 21st birthday whilst Johnnie Beattie was named man of the match during Glasgow's historic 9-6 Heineken Cup win over French giants Biarritz Olympique at Firhill Arena on Sunday. Both players will continue their careers at the club with which they first turned professional.
On both youngsters, Warriors head coach Sean Lineen said: "What a fantastic coup for Glasgow and Scottish rugby.
"Here we have two quality young players who are only going to get better. They will be looked after in Scotland and it is a great example of two players who are eager to stay in Scotland, which will only help strengthen the professional game."
Barclay added: "I did have interest from elsewhere, but I'm happy here and I'm confident that Glasgow are going in the right direction.
"I love the city and I love the camaraderie amongst the squad so I'm delighted to be extending my stay in Glasgow."
Beattie concluded: "Glasgow is where I am from. I love living here and I love playing for my hometown, so it's great news that I will be a Glasgow player until 2010."
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