IT was the must win that they did win.

At this stage of last season's Heineken Cup, a defiant Gregor Townsend emerged from a bruising defeat by Ulster at Scotstoun and insisted Glasgow Warriors could still reach the quarter-finals despite that loss adding to one against Northampton Saints five days previously. Yesterday he conceded the folly of those protestations safe in the knowledge that his side sit just one point behind unlikely group leaders Exeter Chiefs after recording this impressive victory.

In front of a hugely-encouraging crowd of 6047, Townsend's side eked out a much-merited win that leaves them better placed than they might have imagined after two games in Pool 2, given that they are the only side to have travelled to Toulon. That said, their position a point in arrears of both the French favourites and yesterday's opponents ensures that December's double-header against Cardiff Blues becomes even more pivotal after their Rabodirect Pro 12 rivals upset the Heineken Cup holders in Wales on Saturday.

Certainly, this performance, or rather the attritional manner of it, can warm the Warriors ahead of the group games to come. Despite losing to the Scots in Devon during pre-season, Exeter arrived with a lofty reputation - their win in Cardiff last weekend showcasing "the best 50 minutes I've seen from an English side this year", according to Townsend - but left with only bruises and a bonus point. That was enough to take them to the summit of the section, but consecutive contests with Toulon will be a truer reflection of the Aviva Premiership club's chances.

As Townsend predicted they might, Exeter played the more expansive rugby in the opening stages, taking advantage of a prolonged break in the persistent showers to move the ball around confidently, but they could not counter the ferociousness that characterised Glasgow's work. Such determination was perhaps a legacy of last weekend, the hosts having spent much of the intervening period nursing a deep frustration at the manner in which they were eviscerated during the opening half of the defeat in Toulon, but either way their efforts repelled the English for the most part.

Such determination did at times stray beyond the boundaries of legality, though, which afforded Exeter ample opportunity to keep the scoreboard ticking over during a fractious first quarter. Penalties were coughed up for failing to release, side entry and slowing the ball down, with Gareth Steenson confidently stroking between the posts on each occasion. Given that the stand-off was the scorer of a remarkable 239 points last term, such accomplishment would hardly have come as a surprise to Warriors, but perhaps more unexpected was Steenson's sinbinning a few moments later.

With two Ruaridh Jackson penalties having hitherto kept the hosts in touch, they were pressing Exeter back with some vigour in an attempt to restore parity, the visitors grip on possession having slipped with the return of the rain. By now, Glasgow were more comfortably with the ball in hand and created an opening on the left when Niko Matawalu found Gabriel Ascarate. The Argentine, making his Scotstoun debut, was hemmed in on the touchline but had just one white shirt to beat and confidently chipped the ball over his man, only for retreating defenders to thwart his attempts to collect. One of those was Steenson, who was adjudged to have entered from the side and was yellow-carded for his trouble.

The subsequent 10 minutes, predictably, were dominated by the Warriors, but their concerted attacks on the Exeter defensive line were fruitless and Steenson returned with his side's lead intact.

"We were just trying a little bit too much and going a phase too far," said Townsend. "But we realised we had an edge in the lineout and the scrum and I was actually very happy at half-time. I believed the pressure was building and if we kept going something would give, and it did."

It only took four minutes for his belief to be proved correct and for Glasgow to claim a lead for the first time. Having penned Exeter into their own half after a high ball, the hosts turned the ball over and began to build, with Tommy Seymour, Tyrone Holmes and Matawalu all making ground before Tim Swinson breenged under the posts from close range. Referee Romain Poite's decision to consult with the TMO was a formality and Jackson, having missed a penalty a couple of minutes earlier, converted casually.

Monsieur Herve Dubes and his television would play a more significant role later in the half, considering Sean Maitland's overhead pass to be forward before Seymour concluded a slick exchange, but there was no need to get the official involved three minutes later, when Glasgow recorded the score that effectively confirmed their victory.

Maitland again broke threateningly and slipped to DTH van der Merwe, who eluded two Exeter players and released Jackson, whose vision and sleight of hand afforded Holmes - who harbours hopes of a Scotland summons this week on account of Peebles-born father Steven - an easy score.

The conversion took the scoreline to 20-9, but Warriors were left nursing a slight sense of disappointment at the late concession - ratified by the TMO - that allowed the visitors to leave with a bonus point, Dave Ewers bundling over the line after a meaty charge and Henry Slade adding the extras. "That opens it up again and means everyone is still pushing for it," said Al Kellock.

At least this year, Glasgow can consider themselves among that group.