Villa began the campaign with a fine 3-1 win over Arsenal at the Emirates only to follow that with a midweek defeat at Chelsea and a 1-0 reverse to Liverpool in their first home game of the season on Saturday.
But Guzan remains confident for the season ahead and does not expect another battle against relegation.
"I think the improvement is massive (from last year), it's evident to see the change not just on the pitch but the camaraderie and atmosphere that's at the training ground, in the dressing room," he said.
"And that's important because when you go through difficult times on the pitch you have to be willing to fight for each other, and you look around and our performances speak for themselves over the last week, especially against top teams.
"That's credit to what the manager and the coaching staff have done here in terms of changes and, more importantly, credit to the boys who have come in from last season and this season.
"With the players we have and the atmosphere that's been created, going forward we want to try and put together performances we can be proud of and if we do that like we have over the last week then we'll come out the better for it more times than not."