The Spireites have reached the FA Cup fourth round for the first time since 1997, and if there's a Spireite who knows about that year and cup runs, it's Jamie Hewitt.
The Chesterfield-born full back headed in the dramatic late equaliser in the 3-3 draw with Middlesbrough at Old Trafford 18 years ago to force a semi-final replay.
Now on the medical staff at the Proact Stadium, Hewitt talked through the earlier stages of the famous cup adventure of 1997.
“In the third round we were drawn at home to Bristol City," remembered Hewitt. "Like Scunthorpe this year, they were the same league as us but it was a tough game as they’re a big club.
“It was a 2-0 win for us which took us to the fourth round, which in my career I’d never been to. A cup run for us was to get to the second round at that time.
“We got to the fourth round where we drawn away at Bolton who were flying high in the Championship, they went into the Premier League that year so we were massive underdogs.
The similarities of the 1997 and 2015 fourth round ties and striking and, with the Spireites winning 3-2 away at the Trotters back in the nineties, the possibility of an upset on Saturday have clear roots in history.
“In Bolton and now Derby there is a comparison to be made. If we win this one it is a tremendous cup run and we’re getting closer to what we did 18 years ago.”
“It’ll be a great day for the fans, for the players at a great stadium and a very good team in Derby, but we’re playing some good football so we’ll be strong opponents for Derby on the day.”
It's not just past form that will give Saturday's large army of travelling Spireites hope of iPro Stadium glory, as Hewitt explained: “I think we’ve got great momentum at the minute and the team are playing tremendously."
"We’re in a really good vein of form at the minute in the league and obviously in the cup. We’ve played quite a few ties already but are producing it week in week out at the minute, playing some attractive football and winning matches.
“We will be underdogs going to Derby but we’ll give them a good game and I don’t think they’ll be pleased to be playing us, in a way I think they’ll be quite fearful of us.”