After Chelsea acquired Casadei from Inter Milan in 2022 for an initial fee of £12.6 million ($16.24m), with an additional £4.2 million ($5.41m) in potential add-ons, the player spent the first half of the 2022/2023 season with Chelsea's under-21 side before being loaned out to Reading for the second half of the campaign. Last season, Casadei was loaned to Leicester City, where he had the opportunity to work under Maresca. However, his time with The Foxes was cut short when Chelsea recalled him in January. Despite his return, Casadei was used sparingly for the remainder of the season and was more of a bench warmer.