Etherington acknowledged that Stoke's pre-season form and results had been poor, but remains confident they will be ready for their Europa League debut.
Hajduk's spies watched the back-to-back defeats at Brentford and Aldershot last weekend, and Etherington quipped to The Sentinel: "They've probably gone home thinking it will be a walk in the park for them.
"But we are a different animal at the Britannia and it will be all guns blazing.
"We've had a really tough pre-season with a lot of hard work, and it takes a couple of weeks after that to get back into the swing of things.
"A lot of work in a short space of time takes its toll and you need a few days for the body to recover to see and feel the benefits.
"Now I think we are as ready as we can be. We would have liked a bit more time, but the fitness is more or less there now.
"But we also know we have to improve performances because what we are playing against on Thursday is a step up in class.
"It's important how you play tactically. Our manager is usually very good on that and will know how to play on their weaknesses."