London Irish coach Brian Smith admitted his side were in a good place in Pool 1 after a bonus point 41-24 victory over Newport Gwent Dragons at the Madejski Stadium.
They need another bonus point victory in Treviso next week to top the group, while a victory may be enough if Perpignan fail to win with a bonus point at Rodney Parade.
London Irish rattled up six tries with No 8 Richard Thorpe grabbing a hat-trick, securing the bonus point in just over half an hour before relaxing their grip on the game.
Listen to full Brian Smith interview here
"It was job done, it was outstanding getting the bonus point before half-time, but we lost our way a bit in the second half and things loosened up," said Smith.
"The most important thing is that we are still in control of this pool and that is a good place to be.
"We did not pay then enough respect and coughed up some cheap tries in the second half and no-one feels good about a defensive effort like that.
"The first two rounds of this competition we scored six or seven tries, we put six into Newport today, so try scoring is not really a problem for us but game management is.
"We have a young inexperienced back line and if Mike Catt had been on the pitch today we would not have conceded as many points and possibly we would have scored more.
"We cannot get ahead of ourselves. Whether we get five points next week is irrelevant to me, we have to win and we have to get four points which will not be easy.
"Treviso have a big pack and they are playing at home so it will not be easy on the continent - the term 'home touwn advantage' has come for a reason and they have a good record at home.
"They have rattled everyone and their ambition will be to spoil our party and to rattle us."