Glasgow Warriors' Chris Cusiter believes his side's trip to Heineken Cup Champions Leinster on the weekend is the toughest test in European rugby.
The Scotland scrum-half and a veteran of nine season's of European action was delighted with the start the Warriors got against Bath at the weekend but knows this Sunday's trip to the RDS will be a huge challenge.
"A draw over at Montpellier and two points was a good result for Leinster in their opener, but now they will be desperate to get their first win of the Heineken Cup and doubly so on home soil," he told the Evening Times.
"For them there is the added incentive that we beat them at home in the Pro12 earlier in the season, so there is no question we will have to be at our absolute best to get anything. Every-where you look in their team they have quality although any side would miss Brian O'Driscoll who is out injured.
"But we know what we have to do. We must get a better start than we did against Bath.
"The whole of the first half against Bath we were under pressure and Duncan (Weir) and I made a couple of mistakes and couldn't really keep the ball.
"But we turned it around and it is a mark of the way that we are playing right now that we did not play well but still managed to win.
"But we know we will have to improve at Leinster. And the start in particular is going to have to be a lot better.
"We must concentrate on producing the best performance we can on Sunday and if we do that we will give ourselves a chance. If we can pull it off it would rate with anything Glasgow have achieved in Europe."