Glenn has been recovering from a knee injury and played in the Glasgow XV that defeated Scotland U21s at Murrayfield on Monday.
Andy Henderson, Gordon Bulloch, and Cammy Mather are unavailable for Glasgow after being selected for Scotland's Six Nations opener against Wales next week.
Dan Parks has also been selected for the Welsh game, but Matt Williams, Scotland's coach, has allowed the stand-off to play against Ospreys, though only for the first part of the match.
Colin Gregor, Watsonians' stand-off, is expected to make his Glasgow debut. The 22-year-old, a former pupil of Glasgow High School, has been brought into the Glasgow squad as reserve outside half as Calvin Howarth is out with a shoulder injury. Colin played for Glasgow in Monday's victory over Scotland U21s, slotting four kicks in difficult conditions.
Alan Bulloch, Sam Pinder, Scott Lawson, and Andrew Wilson return and Jon Petrie takes over as captain from Cammy Mather.
Graeme Beveridge (ankle) and Rory Kerr (knee) are unavailable because of injuries.
Glasgow team
15 Glenn Metcalfe
14 Gareth Maclure
13 Graeme Morrison
12 Alan Bulloch
11 Sean Lamont
10 Dan Parks
9 Sam Pinder
1 Euan Murray
2 Scott Lawson
3 Lee Harrison
4 Andrew Hall
5 Nathan Ross
6 Andrew Wilson
8 Jon Petrie (captain)
7 Donnie Macfadyen
Replacements:
16 Simon Gunn
17 Andrew Kelly
18 Joe Beardshaw
19 Paul Dearlove
20 Kenny Sinclair
21 Colin Gregor
22 Moffat">Stuart Moffat