But the Warriors have lost just once at home to Leinster since 2007, 23-16 in the European Cup at Firhill in January 2012, even if they have had to draft in Gala No.9 George Graham to the bench.
And Townsend, who welcomes back hooker Pat McArthur, prop Moray Low and winger DTH van der Merwe from injury, has every faith that the youngsters will rise to the challenge.
"It's certainly unusual to have all our four scrum-halves unavailable at the same time but I've been very impressed with Sean since he joined us," Townsend told glasgowwarriors.org.
"His work ethic and attitude in training are excellent and, even with those other players available, he would be pushing for a starting place.
"George has come in and been very professional in his approach to training. It's a great experience for him as he has impressed a lot of people this year with his performances for Gala.
"In our last game here at Scotstoun we kept up our winning run through some ambitious attacking play allied to strong defence, and that was a great way to enter the international break. But we know as we enter the middle third of the season that it's going to get much tougher, starting with Leinster.
"They are an exceptionally good side and will be desperate to close the gap in the table to the top four."
Townsend is also able to call on the bulk of the players who were called up for international duty over the last two weeks with Peter Murchie, Tommy Seymour, Alex Dunbar, Tom Ryder and Ruaridh Jackson all starting for the Warriors.
Leinster meanwhile, have been boosted by the return of Sean O'Brien who makes his first RaboDirect PRO12 appearance of the season in an all-Ireland back row that also features Shane Jennings and Kevin McLaughlin.
Joe Schmidt can also welcome back both Isa Nacewa and Ian Madigan back from injury while Leon Cullen leads the team and partners Quinn Roux in the second row.
And Aaron Dundon makes his first appearance at hooker since picking up an injury in the opening round of the league campaign.
Leinster's four game winning run in all competitions ended at Ospreys in round eight of the RaboDirect PRO12 but Jennings is determined to get back to winning ways and keep pace with the top four with Schmidt's side currently sixth in the table.
"We're looking forward to the game and we're keen to get cracking," said Jennings.
"It's great to see some of the boys back from injury, the more the merrier.
"It's always tough to go to Glasgow, they've got a good squad and they're a very dangerous side so we have to make sure we don't let them get too much of the ball.
"We're not that happy with how we've performed but we're in touching distance and if we put in a good performance we're going to stay in the hunt."
At Scotstoun Stadium , 7.35pm.
Referee: Neil Hennessey (WRU, 13th competition game)
Assistant Referees: Andy Macpherson, Bob Nevins (both SRU)
Citing Commissioner:Iain Goodall (SRU)
TMO: Andy Ireland (SRU)
Live on BBC ALBA and RTE Sport