Palace go into the game after losing their opening two Premier League games.
Glasner said, “We have to prove it.
“I don't want to say yes or no. We have to prove it, and we will see at the end of the season if we are better than last year. If we score more goals, we are better in offence, and if we concede fewer, we are better in defence, and then we have more points.
“And if we don't do this, if we don't work as a team, if we don't work hard every training session, if we don't improve, we will be weaker.
“It’s not so difficult, but again, we have a great squad, we have great players with a very good spirit in our team, so the basement is here now. Then, it's our jobs – all our jobs, not just the staff's jobs, but also the players' jobs – to use this basement and build a great building.”
Glasner added: “For me, regardless of which team we play against, we look at what we want to do, we look at our performance, I always want that we perform as well as possible, because this increases the chances to win the game.
“We also have to be honest that we know we are Crystal Palace. There are many teams in the Premier League who have more money, who spend much more money than we did, and than we can, and we have to accept it.
“But that doesn't mean that we don't have a chance. I think we showed it last season, and many times in my career, we showed it with all our teams, that you also can win against bigger teams if you have a good spirit, if you have a good plan, if you believe in yourself.
“If you work very hard together, it's possible. And this is what we will try on Sunday.”