Nick Evans says there is no room for complacency despite Harlequins being on the verge of Heineken Cup progress.
Quins have won all four of their pool matches and know victory over Connacht on Saturday will see them move closer to securing a home quarter-final.
The 32-year-old fly-half told BBC London 94.9: "We know the calculations and permutations of what can happen.
"But we are under no illusions what is ahead of us and what the Heineken Cup can throw up."
Evans added: "We will have to be right at the top of our game and take the opportunities which present themselves."
Last season Quins missed out on a quarter-final berth when they lost their final group match to the Irish side.
"Connacht are a hugely physical and a very good side who have a good set piece and have really developed as a club," the former New Zealand international continued.
"Ahead of the game [in training] we will clean up the areas we feel we need to clean up.
"It is a fantastic opportunity for us and we need to make sure we are at the top of our game to make sure that we nail it.
"We want to put ourselves in the position where we give ourselves the best opportunity.
"If we can have a platform to get into the quarter-finals, anything can happen from there."
Meanwhile, Evans says the side have been working on ways to make sure they can continue play their attacking brand of rugby, even when opposition sides set out to disrupt their play.
"Teams are coming at us to try and slow our ball down, especially at the ruck," Evans said.
"It is for us to be really accurate and precise to get quick ball. In that respect the onus is on us.
"We always want to play our style. We've been working really hard on how we deal with teams frustrating us.
"We know teams are going it do it so it's how we manage that and turn slow ball into quick ball.
"There are lots of ways to create tempo and means we have to concentrate of different parts of our game."