Chelsea are currently at the top of the table after five matches, but Villa are only three points behind following their strong start to the season.
Despite Jose Mourinho's side being favourites to win the match at Stamford Bridge on Saturday, Guzan believes that the visitors have what it takes to come away with a positive result.
"Chelsea have a top defence and a top goalkeeper but they have obviously still conceded goals this season," the USA international told the club's official website.
"With the strikeforce that we have, there's no doubt in my mind that we can cause them problems and ask some very good questions."
Guzan has played in all five of Villa's matches in the Premier League so far this season.