Calderwood told the club's official website www.nottinghamforest.co.uk: "I went into the dressing room to speak to their manager and congratulate the players because I thought they were excellent.
"We knew we would have to work for it. A lot of people will respect Salisbury for the manner in which they have played over the two games.
"They didn't come here and try and turn the game into a war or a tactical battle - they came to play and that speaks volumes for them."