GREGOR TOWNSEND'S reign at Glasgow arguably could not have begun with a more daunting challenge than a trip to Ravenhill but the head coach admitted he was frustrated, although not downhearted, by the manner of his side's defeat in their opening RaboDirect PRO12 match.

The most disappointing aspects were the malfunction of the Warriors' set-piece and Ulster's dominance in terms of relentless physical prowess up front that robbed Glasgow of the platform to play the high-tempo attacking game Townsend wants.

He said: "I can't fault the effort from the boys but there are non-negotiables and, for me, these were the set-piece and line-out in particular, and the conceding of 16 penalties compared to Ulster's nine."

Against a side who are also in Glasgow's Heineken Cup Pool, Townsend opted to leave Scotland internationalists John Barclay, Chris Cusiter and Ryan Grant on the bench in favour of the youthful brio of Chris Fusaro, Henry Pyrgos and Gordon Reid.

With the defences on top early on, Warriors were first to infringe when hooker Finlay Gillies was penalised for going in at the side. Replacement Niall O'Connor put Ulster 3-0 up after 10 minutes with his first kick of the game. When a Warriors drive was illegally ended three metres out the Italian referee Marius Mitrea awarded a penalty that Duncan Weir slotted cleanly from in front of the uprights to restore parity at the end of the first quarter.

The Warriors' defence was starting to creak and their penalty count mounting under Ulster's superior weight and physicality, but O'Connor's profligacy with two close-range penalties let them off the hook.

However, Glasgow's hopes were dealt a twin blow when captain Al Kellock limped off, with James Eddie replacing him, and Tommy Seymour received a yellow card for persistent infringing. With two minutes of the first half to go, the inevitable try arrived when Michael Allen clinically surged over on the left flank. O'Connor missed the conversion to allow Glasgow to turn around just 8-3 down.

Townsend sent on Cusiter at scrum-half and Grant at loosehead as he attempted break the Ulster stranglehold on the game, but disaster was lurking just round the corner

Four minutes after the interval, with Glasgow deep inside Ulster territory and threatening, Craig Gilroy intercepted a loose Weir pass for a breakaway try, with O'Connor finally slotting the follow up kick to make it 15-3.

Weir's replacement by Ruaridh Jackson at stand-off was indicative of his increasing toils. Despite struggling at their own line-outs, where the absence of Kellock hit hard, Glasgow stuck to their task.When Seymour broke down the right wing and side-stepped Allen to score, and Jackson converted, Warriors were back within striking distance of opposition.

But with Glasgow now on the front foot and scenting an unlikely victory, another loose pass coughed up possession that ultimately led to a penalty which O'Connor converted.

Ultimately, Townsend's gamble in keeping most of his big guns on the bench, undercooked as they may have been after an extended break following Scotland's summer tour, and then using them to change the momentum of the game after the break, came up just short.

Yet the indefatigable fight-to-the-death Warriors spirit remains and one suspects that next week, for Glasgow's historic first-ever game at their new Scotstoun home, Townsend will have the balance right after these opening-night lessons.

He added: "The breakaway try when we were on the front foot really killed us but I thought we showed immense resilience to keep going and almost pull them back.

"Even in defeat we have given ourselves a platform for next week's home game. It is just so frustrating to lose the bonus point because we were going all out for the win."