In the midst of the RBS 6 Nations, backs Dan Parks and Andrew Henderson are rested alongside two of the 'three Bees', John Barclay and Kelly Brown, having been involved with the national team against France and Wales, paving the way for Forrester to make the cut above some other big influences in the Glasgow squad.
Lineen said: "Donnie Macfadyen has just returned from injury so we don't want to throw him straight into what will no doubt be a very physical game.
"Also, James Eddie has been away from Glasgow with the Scotland A squad so Calum has had the opportunity to impress during preparations and he's certainly done that.
"Calum has played a few game for us before so we know what kind of player he is and the potential he has so I'm pretty excited about seeing how he does on Friday night."
Looking forward to a big weekend, Forrester said: "It's a great opportunity for me to be involved this weekend. The Warriors have a good reputation in Europe for the quality of its back-row so it's pretty exciting to be part of it.
"The National Academy has been great for me because I've recovered from an injury over the summer and gone on to play international sevens as well as being involved with the pro-team back up games before Christmas.
"I've been on the bench a few times for Glasgow which was great but making the starting XV is that next big step."
In addition to Forrester, Lineen has called up another young Scottish talent in Ruaridh Jackson who takes his place on the bench.
Glasgow Warriors team to play Llanelli Scarlets at Stradey Park in the Magners League on Friday 15 February (kick-off 7:10pm)
15 Bernardo Stortoni
14 Lome Fa'atau
13 Graeme Morrison
12 Daryl Gibson
11 Hefin O'Hare
10 Colin Gregor
9 Sam Pinder
1 Justin Va'a
2 Fergus Thomson *
3 Moray Low
4 Andy Newman
5 Alastair Kellock CAPTAIN *
6 Stevie Swindall
7 Calum Forrester **
8 Johnnie Beattie *
Substitutes
16 Dougie Hall
17 Ed Kalman
18 Dan Turner
19 James Eddie
20 Ruaridh Jackson **
21 Scott Barrow
22 Max Evans
* = Member of Scottish Institute of Sport
** = Member of Scottish Rugby's Senior National Academy
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