Set to debut for 2015, the new Jaguar will be smaller than the XF and, along with the 3 Series, face off against rivals such as the Audi A4 and Mercedes C-Class. Sources claim that base XS will come with a turbocharged four-cylinder engine along with an optional supercharged V6. Our spy photographers tell us this particular test mule is equipped with a diesel engine but it’s unclear whether that’ll be a Europe-only option. In addition to the base models, expect for Jaguar to also do a high-performance R version to take on the M3. Also expect for the XS to eventually spawn wagon and crossover variants.