The latest reports claim that the two Japanese automakers will collaborate on sports cars - plural - with Toyota leveraging Mazda's inline-six engines for a next-gen GR Supra and its lightweight compact sports car expertise for the next-gen GR86. They are just rumors at this stage, it must be said, but my concern if they prove to be true isn't whether a GR86 can share bones with a Miata - I know that can work - but what it means for Subaru's performance car lineup.