What is this keepers shirt?

[IrelandsRover]

Spotted this on eBay. Doesn’t appear to be a knock off. Exact same style as the actual jersey of the time except the badge is centered and ASICS logo is at the back. Does anyone know if this is legit? Perhaps a training jersey? 
I have no intention of paying the £100 for it, just curious 

[Herbie6590]

That design was used as a keeper’s shirt by Asics, the Asics logo presented like that on the reverse was popular with a lot of training kit at the time, the centred badge didn’t arrive on playing kit until the Uhlsport days so I would guess that this is a prototype or a manufacturing error ?‍♂️

[IrelandsRover]

3 hours ago, Herbie6590 said:

That design was used as a keeper’s shirt by Asics, the Asics logo presented like that on the reverse was popular with a lot of training kit at the time, the centred badge didn’t arrive on playing kit until the Uhlsport days so I would guess that this is a prototype or a manufacturing error ?‍♂️

Thanks Herbie6590