The USA international points out that, although Arsenal came more into the game in the second half, he did not have a save to make and says the whole team is to thank for that.
"In the second half I didn't have a save to make and credit for that goes all the way through the team. The way the whole team worked, pressurised in midfield and when they had the mini-breaks, the way we got back and made it difficult for them was fantastic.
"It's difficult to recreate these games because it is such a big game, but if we can continue with that frame of mind and that workrate throughout the team there is no reason why we can't go on from here."
Kasey is another to pay tribute to the backing the team received from the crowd on Sunday - he feels it will be difficult to improve on.
"It can be repeated but it can't be bettered! It's a huge game and playing as well as we did in the first half - we're a couple of goal line clearances from being 3-0 up.
"That's a very good statement to how far we're moving up because they are one of the best teams in the world, as they've proved in the last couple of years. You can only gauge yourself against the best and this time we were better."
Kasey Keller says the way the team performed against Arsenal on Sunday is hopefully a statement of intent for the rest of the season.