"We won this leg but maybe we were lucky considering the amount of chances they created in the first half," said Rijkaard.
"We tried everything possible and I am proud of the spirit and effort my players put in.
"They worked hard and tried everything but Liverpool are a difficult team to play against.
"They are strong and mentally tough. That is the way it goes. Sometimes it is like that in football however hard you try.
"I can only congratulate Liverpool, they are a vigorous side and for the neutral it must have been a game full of good attacking football.
"From Liverpool it was a great performance. Their style is very difficult to play against. We tried everything, although we were not at our best.
"We fought to the very last seconds but Liverpool were highly motivated and they defended in such a way to stop us getting close to their goal.
"Anfield is such a difficult place to play in, so we are out, but I was very impressed with the spirit and fight we showed. I now expect to see that for the rest of the season."