Swollen wheel arches seem to give it much more visual aggression than the eight-year-old outgoing car, and the profile looks to be less top-heavy, too. That's a clear indication of the car's TNGA platform architecture - modular underpinnings that are also shared with the Corolla, Camry and C-HR.
Another prototype with a different camo and wheel design was spotted at the 'Ring at the same time, suggesting the Japanese firm is trialling two different chassis set-ups. It is likely that the one in the red camo is a GR Sport variant, Toyota's new trim designation for models with a sportier tune to bridge the gap between mainstream variants and the full-fat GRMN flagship.
Also on test was a hybrid variant, determined because of the legally mandated yellow sticker that must be installed on all electrified test vehicles.
Toyota's UK sales are overwhelmingly biased towards hybrid models, so a petrol-electric variant should continue to be the volume seller. It's possible that the 2020 Yaris will also come with a straight petrol version, however, more suited to sporting variants.