Glasgow sit second in the RaboDirect PRO12 after 13 games but have failed to transfer their form into the Heineken Cup and lost their fifth pool game against Ulster on Friday.
Glasgow lost 23-6 at Ravenhill and have still to register a win in this season's competition with just one more game to go against Northampton at Scotstoun.
"We're very disappointed with the way it has gone in Europe," said the Glasgow skipper. "We've let ourselves down. We're sitting second in the PRO12 which is fantastic but there is a lot of work to go.
"We wanted to push on in the Heineken Cup and show the quality we have in this squad and we went to Ulster for the win but we didn't quite measure up.
"I thought we got our tactics spot on in the middle third of the game, but credit to Ulster for the way they came back into it.
"We are disappointed with the tries we gave away, soft tries, they didn't have to work too hard to get them. You can't come to Ravenhill and give away soft tries."