A player version, sometimes marketed as an authentic shirt, is a higher-performance version of a shirt design. Depending on the manufacturer and season, it may feature lighter materials, a more athletic fit, different ventilation zones and heat-pressed badges. Some player versions are sold commercially, meaning supporters can purchase them directly from retailers.
A match issue shirt, on the other hand, is defined by its intended use within a team. It is supplied for the club's players or squad rather than simply being a premium version sold to the public. The two categories can overlap in their construction. A match issue shirt may be based on the same player version that is available commercially, but it can also feature additional team-specific details or differences in materials and construction.
For example, a commercially available player version might have a conventional care label inside the shirt, while a team-supplied version has its washing instructions printed directly onto the fabric. In other cases, the differences may be more subtle and require a close comparison with the retail version from the same season.
The terminology used by manufacturers can add to the confusion. Nike, Adidas and Puma all produce performance-oriented football shirts, while brands such as Umbro, Kappa and Macron also supply professional teams with match kit. The names used for retail performance versions vary between brands and seasons. Terms such as Authentic describe a product specification; on their own, they do not prove that a particular shirt was supplied to a club for a match.
The key difference is that a player version describes the type of shirt, while match issue describes its intended destination and use, which is for official games.