Speaking to ITFC.co.uk, Magilton said: "It was important for the players to get another win under their belts to build on last week's victory at Derby and although it was a scrappy performance, we will take the place in the next round.
"Credit to Chesterfield, they gave it a real go and caused us some problems but I thought our back four and 'keeper did very well.
"Ivan Campo showed his experience and his class with his composure on the ball and it was good to get another clean sheet.
"Pablo and Jon Stead took their goals well and we need to take the confidence we will get from the win into next Saturday's game against Sheffield Wednesday."