Macfadyen suffered a leg injury during the Warriors' pre-season friendly against London Wasps at Adams Park back in September and recently prove his match fitness when he featured during the Warriors' back-up team victory over Edinburgh at the beginning of last month.
The longest serving member of the Warriors squad, Macfadyen said: "The Ospreys are doing really well just now and have made a massive contribution to the current success of Welsh rugby.
"Being out of first team rugby for some time has been very frustrating, but this is a fantastic opportunity to come back and help regain our momentum going into what is the business end of the season."
In the backs, the elder of the Evans brothers, Max, also features in the starting line-up fresh from his double try-scoring debut for the Scotland 'A' team.
Evans said: "The last few weeks have been great for me. Being involved with the Scotland A team has been really beneficial and given me so much confidence going into this game.
"I'm optimistic that we can pull off a shock result on Friday and get our season back on track."
On the visit of the league champions, Warriors head coach Sean Lineen, added: "Due to the international break, it's been a fairly long six weeks since we were last here playing in front of our home support.
"Our last game, against Saracens in the Heineken Cup, saw us in with a chance of progressing through to the knock-out stages for the first time. We now have to take the lessons learnt from that experience and finish our season off in style, starting with a massive challenge tomorrow night against the Ospreys."
Glasgow Warriors team to play the Ospreys in the Magners League at Firhill Arena on Friday 29 February (kick-off 7:30pm)
15 Bernardo Stortoni
14 Lome Fa'atau
13 Daryl Gibson
12 Graeme Morrison
11 Max Evans
10 Dan Parks
9 Sam Pinder
1 Ed Kalman
2 Fergus Thomson *
3 Moray Low
4 Andy Newman
5 Alastair Kellock CAPTAIN *
6 James Eddie
7 Donnie Macfadyen
8 Johnnie Beattie *
Substitutes
16 Eric Milligan
17 Kevin Tkachuk
18 Dan Turner
19 John Barclay *
20 Colin Gregor
21 Scott Barrow
22 Hefin O'Hare
* = Member of Scottish Institute of Sport
Tickets for the game are still available, priced £15 for adults and £5 for concessions (under 18s, students & OAPs), and can be purchased by calling the Ticket Hotline on 0844 800 3490 or by logging onto www.glasgowwarriors.org
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