Tickets for tomorrow night's game - priced at £15 for adults in advance with a new AnyGame voucher (£20 on match days), £10 for concessions (including students) and £5 for under 18s - can be purchased now by calling the Ticket Hotline on 0844 800 3490 or by logging onto www.glasgowwarriors.org.
Glasgow Warriors' new AnyGame Vouchers have been introduced to encourage supporters to buy early and, to avoid queues, are not for sale or collection on match days.
McCall, a Scotland 7s internationalist, gained previous Magners League experience when he made three appearances for Edinburgh back in season 2006/07, however, he is now delighted to be back in the professional ranks - this time in Glasgow colours.
"I was really grateful when Sean [Lineen] called and discussed joining Glasgow on a training contract," said the 22-year-old. "I've really enjoyed being part of the squad and feel that being out of the professional game for a few years has reinforced my appetite for the game at this level.
"The Ospreys are a quality side and I'm really looking forward to getting another opportunity to perform in the Magners League."
Looking forward too seeing his new recruit make his Glasgow debut, Warriors head coach, Sean Lineen said: "Dave has had a great pre-season and has fitted into the squad very well. He is a real athlete and has matured a lot over the past few months.
"Not only will he be up against a side full of internationals, but littered with British Lions as well. It'll be a massive test for him but I'm confident that he's got the goods."
The Ospreys have lost three of their last four games in the Magners League and have won just one of their last four visits to Scotland and Lineen is hoping that the Warriors can extend the list of defeats on Scottish soil.
"We have to take what happened last week [a 30-19 away loss to the Dragons] on the chin. We've had two good wins at home but that's not to say we don't have to work for another.
"We're up against a really tough outfit but the players have worked very hard this week and it's vital we get a big vocal crowd along to cheer us on."
Lineen has reversed all six of the changes he made for last weekend's away defeat to the Dragons. The only difference from the line-up that recorded victories over Munster and the Scarlets at Firhill in the opening fortnight of the competition is McCall replacing Peter Murchie.
Glasgow Warriors team to play Ospreys in the Magners League at Firhill on Friday 25 September
15 Bernardo Stortoni
14 Rob Dewey
13 Dave McCall
12 Graeme Morrison
11 Thom Evans
10 Dan Parks
9 Chris Cusiter
1 Jon Welsh
2 Dougie Hall
3 Moray Low
4 Tim Barker
5 Alastair Kellock CAPTAIN
6 Kelly Brown
7 John Barclay
8 Johnnie Beattie
Substitutes
16 Fergus Thomson
17 Kevin Tkachuk
18 Dan Turner
19 Richie Vernon
20 Mark McMillan
21 Colin Gregor
22 Hefin O'Hare
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