Gregor said: “It’s a huge game for the club, even more so after our defeat to the Scarlets last week. We expect a reaction from our players tomorrow night.
“There have been a lot of memorable moments at Scotstoun this season and this has the potential to be another great game. We’re really respectful of our opponents, they take a combative approach to every game, they challenge at the breakdown, have an excellent set piece and are ranked as the best defensive team in the competition.
“It’s a wonderful challenge for our players – going up against a top quality side in front of their home support.
“A number of players have been given the opportunity to represent the club in such an important fixture and it’s worth highlighting the inclusion of Graeme Morrison, who has been a tremendous servant for the club over the past 10 years. He has had injury issues this season but been training really well in recent weeks and we’re delighted to have him back in the team.
“It’s great for Graeme to line up alongside his good friend John Barclay, who we know will be playing what could be his final home game for the club on his 150th appearance, which is a tremendous achievement.”
The Warriors back three is made up of Stuart Hogg at full-back, Sean Maitland on the right wing and Sean Lamont, who replaces DTH van der Merwe on the left.
Alex Dunbar comes in for Mark Bennett at outside centre and Graeme Morrison starts at inside centre.
Duncan Weir replaces Ruaridh Jackson at fly-half and Nikola Matawalu comes in for Henry Pyrgos at scrum half.
In the forwards Ryan Grant starts at loose head in place of Gordon Reid, Pat MacArthur continues at hooker and Moray Low once again starts at tight head.
Captain Alastair Kellock combines with Tim Swinson in the second row and in the back row Robert Harley starts the game at blind-side, with Ryan Wilson dropping to the bench. Josh Strauss moves from blind-side to number eight.
John Barclay once again starts at open-side in what could be his final home game with the Warriors after 150 appearances for the club. John is moving on at the end of the season.
The Warriors have Dougie Hall, Ofa Fainga'anuku, Ed Kalman, Tom Ryder, Ryan Wilson, Henry Pyrgos, Peter Horne and DTH van der Merwe in reserve.
15 Stuart Hogg
14 Sean Maitland
13 Alex Dunbar
12 Graeme Morrison
11 Sean Lamont
10 Duncan Weir
9 Nikola Matawalu
1 Ryan Grant
2 Pat MacArthur
3 Moray Low
4 Tim Swinson
5 Alastair Kellock (Captain)
6 Robert Harley
7 John Barclay
8 Josh Strauss
Substitutes
16 Dougie Hall
17 Ofa Fainga'anuku
18 Ed Kalman
19 Tom Ryder
20 Ryan Wilson
21 Henry Pyrgos
22 Peter Horne
23 DTH van der Merwe
Not available for selection through injury:
Michael Cusack (shoulder), Chris Cusiter (shoulder), Chris Fusaro (groin), Finlay Gillies (neck), Rory Lamont (ankle), Jon Welsh (groin)