Head coach Joe Schmidt insisted his Leinster side have a long way to go in the defence of their Heineken Cup title after qualifying for the knockout stages with a 23-16 win over Glasgow Warriors at Firhill.

The Dublin-based side are seeking to become just the second team after Leicester in 2001 and 2002 to successfully defend the European title and today reached the quarter-finals by clinching victory in Pool Three with one match to spare.

Schmidt said: "We were just one of 24 contenders. After next weekend there will be eight contenders.

"We're delighted to be one of those eight. As far as defending, it's not just defending the Heineken Cup. You've got to roll up your sleeves and go out and win it again."

Since the opening draw with Montpellier, Leinster have now won four straight games and host the French side in Dublin next Saturday safe in the knowledge that they cannot be overhauled at the top of Pool Three.

Rob Kearney and Isaac Boss scored second-half tries as Leinster finally overcame the Warriors' stern defence, while Jonathan Sexton kicked one penalty and Fergus McFadden two penalties and two conversions.

Flanker Sean O'Brien was sin-binned four minutes from time, but Leinster's defence, which had been strong throughout, held firm to seal their progress.

Leinster have not lost in European competition since December 2010 and are seeking victory next weekend to claim a home tie in the last eight.

Schmidt added: "I'm delighted to get the result today. I know there were imperfections in the performance and I know my players have gone on record saying I'm always fussy.

"I don't really care about the imperfections today. I just think you deserve to be proud of what you did.

"You deserved to get the four points and we'll come away from this, glue ourselves back together in six days' time and front up at the RDS in front of a full stadium and try to chase that home quarter-final that we really, really want."

Ireland fly-half Sexton deferred kicking duties to McFadden due to an ankle knock, but was instrumental nonetheless, his cross-kick fielded by Kearney for a score early in the second half which turned the game in the visitors' favour.

Schmidt added: "It was every bit as tough as I expected. "We knew the game would be a battle of attrition and that's pretty much the way it proved."

The Warriors, who earned a losing bonus point, were always within striking distance, but Leinster's class told.

Duncan Weir kicked 11 points, while replacement Colin Gregor touched down for a try.

The Warriors play Bath at The Rec next weekend knowing victory is a must if they are to keep their European ambitions alive this season in the second tier Amlin Challenge Cup.

Glasgow head coach Sean Lineen said: "Leinster are not the Heineken Cup champions for nothing.

"I thought we stood toe-to-toe with them for long periods of the game.

"One bit of class from Kearney, try. We had two guys there, but he got the ball. That's just class."