Replacement key

[Shnozz]

My Exige came with a second key. Never thought to try it other than the electronics, which lock and unlock the car as they should. However, having grabbed the "wrong" key off the side the other day I have now discovered it doesnt work in the barrel - placing it alongside the "right" key and I see that its a different cut.

Not quite sure how its come to be but is there a way to just swap over the actual key section given the electronics side work as they should?