Chesterfield manager Paul Cooke has signed Sam Clucas from rivals Mansfield for an undisclosed fee.
Clucas, who was into the final 12 months of his contract with the Stags, has put pen to paper on a two-and-a-half year deal with Cook's side.
Talks between the two clubs regarding the 23-year-old had been going on for almost a month, with Mansfield turning down an offer from the Spireites last week.
However, an improved bid was accepted on Monday afternoon and the winger made the short trip to the Proact Stadium that evening to finalise his switch.
Clucas was not signed in time to feature in Tuesday night's Johnstone's Paint Trophy tie at Scunthorpe.
With Chesterfield's Sky Bet League One fixture against Swindon this weekend postponed due to international call-ups, the earliest possible time the former Hereford man could make his debut is when the Iron visit the Proact Stadium in the league on September 13.
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