He may harbour something of a soft spot for Exeter Chiefs but Gregor Townsend is well aware that the men from deepest Devon will be far from soft touches.

One game into the six-match Heineken Cup group stage and already the phrase "must win" is being tossed around like a ba' in the warm-up. There is no time to find your feet in this competition, of course. Glasgow Warriors were knocked off theirs and trampled into the ground by a thunderous Toulon during the first half of last weekend's encounter in France.

This Sunday, they are eager to put the boot in themselves and kick-start their campaign. That will be easier said than done. Exeter, who are in sixth place in the Aviva Premiership, will travel north in buoyant mood after launching their Pool 2 assault with a rousing 44-29 victory over Cardiff Blues during an eye-opening and eye-catching performance.

"My brother, Craig, played and coached with Exeter so I've always had a bit of a soft spot for them," confessed Townsend, the Glasgow head coach. "It's been great to see them come up the divisions and get better and better."

The respect he has for this weekend's opponents is clear. The warning signs are there for all to see, too. "Last week, Exeter's first 50 minutes against Cardiff was the best I've seen from an English side in the last year," added Townsend. "It was a lesson in how to look after ball, a lesson in passing, in pace on the ball, in contact work; they were relentless. They know what they're about and they are certainly not scared of moving the ball in their own 22. They remind me a lot of Leinster last year [who won the RaboDirect PRO12 title]. They are very good on the breakdown, they will keep ball and put you under pressure."

In the head-scratching aftermath of the Toulon defeat, the coals of that first-half collapse have been raked over with remorseless detail and there have been more postmortems on the performance than you would find in an entire box set of Quincy episodes. Dougie Hall, the veteran Warriors hooker, had suggested the other day that "heads will roll" and Townsend has shuffled his pack for the vital fixture with the Chiefs.

DTH van der Merwe, the Canadian internationalist, has been handed a start having emerged from the bench last Sunday to bolster Glasgow's second-half salvage operation with a brace of tries. Gabriel Ascarate, the 25-year-old from Argentina, will make his home debut in the centre alongside Byron McGuigan after Alex Dunbar was sidelined with a niggling neck injury. "There's a bit of nerve damage," added Townsend.

Niko Matawalu, the Fijian whose shift to the role of scrum-half against Toulon also helped transform Glasgow's fortunes, will hold on to the No.9 shirt and make his first appearance at Scotstoun this season while, in the pack, Pat MacArthur, Ed Kalman, Tyrone Holmes and Rob Harley all come in to the starting XV. "After a defeat like that, we know how important the pack's performance will be this weekend," the Glasgow coach noted. "We learned a great deal last weekend in Toulon, about ourselves and the level of rugby we face in this competition.

"The display from our players after half-time was excellent but there is still an underlying feeling in our group of frustration and determination to put things right.

"The first half there showed what happens when you don't turn up against the best teams. The second period demonstrated what happens when you do the fundamentals right, have a go and execute things well. The fact we scored four tries to gain a bonus point is something to take heart from.

"This time last year, we played a good game down at Northampton but missed out on a point. We are better off than we were a year ago so it's important that we show what we are really about this weekend. Every Heineken Cup is a big game. Teams tend to play much better than they do in their own tournaments. It's only six games and they throw everything at it. We are well aware that if we don't get anything out of this game then it's going to be very tough to get through our pool."

The Chiefs are coming, but the Warriors are bracing themselves for the fight.