Gerard Houllier has warned that Liverpool's route to the Uefa Cup semi-finals is paved with danger.
After seeing his Anfield heroes force a creditable 0-0 draw away to a Porto side who have now gone a year since losing on their own ground in any competition, the Liverpool manager immediately played down the euphoria.
Houllier said of next week's second leg: "They can break us - they will have more space away and they will push us more."
It was a timely warning that a goalless first leg is not the glorious passport to two-legged success it at first seems.
Houllier said: "They can score away, they have proved that in the last round against Nantes. They are a fine attacking side and they will be very dangerous at our ground.
"They have the quality to score away from home, they are so dangerous. We will have to keep on our toes to avoid that."
But Houllier did accept that Liverpool's defiant display deserved praise. He added: "It is always a good result when you draw away in Europe, we defended superbly and the one thing we could have improved on was the way we used the ball in attack.
"But it was still an outstanding display by our defence. But we did not do as well when we did have the ball in attack, we failed to make the telling final pass.
"We had a couple of early chances to do that, and we could have scored, but we failed to make the best use of the ball we did have.
"I must emphasise that it is only half time, we have 90 minutes left and even though that is at Anfield, but we now understand why Porto have not been beaten on their own ground for so long.
"However, we showed composure which is good for the progress of our side for the future. In away first legs you can hold onto your chance, you can improve it like we did in Rome or you can blow it and lose badly.
"I would only say that what we have managed to do is to hold on to our chance, we still have a very difficult home leg to come against a highly dangerous team."