Liverpool defender Virgil Van Dijk has admitted his delight at securing a clean sheet against Porto.
The Reds were at their best going forward in a 2-0 win, but they were also very solid at the back.
And Netherlands international Van Dijk knows that not conceding an away goal is critical in such ties.
"To score two good goals was very important, but to keep the clean sheet tonight was the most important thing, so we have something to build on," said Van Dijk to reporters after the game.
"We kept pressing, we kept going, we played very well I think.
"In the second half, they tried to change it up a bit, there were some moments of danger, but I don't think any clear chances.
"It's a good result, if we score one, it's going to be even more difficult for them to go through.
"We're going there to play our game and we will create chances and finish them off hopefully.
"It's going to be tough because their fans are pretty extreme, like here, so I'm definitely going to enjoy that."