"The team has been working really hard and the new players have adapted well," said the forward.
"The last three games we have had some good results against Rangers, Valerenga and Lazio, but let's see where we are after this week. If we start well on Wednesday and then against Sunderland in the Premier League on Saturday, then we will have had a good pre-season.
"We know that we are a good team. We have a lot of confidence and we've just got to show that in the first games of the season.
"I know a bit about Liege. Belgium is close to Holland and I know their league. Maybe it isn't as good as a couple of years ago but they are still a good team with a few talented young players.
"It will definitely be tough for us and hopefully we can get a good result. I think it's really important to have the second game at home. Every team in Europe is difficult to beat but it's good for us because the distance is not too far. Hopefully we can get the result we want and get through to the Champions League.
"This is a really important game for us so early in the season because we know if we were to lose we would be out of the Champions League. That's not what we want because we have had some really good results in that competition over the past few years."