This is the new Castore Feyenoord 23/24 Away shirt.
The Rotterdam-based Dutch Eredivisie champions 2023-24 primary-change release has tonal blue patterning throughout - with the exception of small panels on the shoulders, the neck and cuffs - and this is intended to nod to the city’s architecture.
Embellishment beyond this is in white - even the crest has been converted to this design’s palette - and the kit is marketed as being completed with navy-blue shorts and white socks, although white shorts have also been produced.
View the: Feyenoord 2023-24 Away Kit