An exterior sideview mirror system includes an exterior sideview mirror assembly including a plano-auxiliary reflective element having a rearward field of view when attached to a side of an automobile. The plano reflective element and the auxiliary reflective element are mounted adjacently at the reflective element assembly in a side-by-side relationship and not superimposed. The plano reflective element and the auxiliary reflective element are supported at a backing plate element. The rearward field of view of the auxiliary reflective element may be different from and angled to the rearward field of view of the plano reflective element. The plano reflective element and/or the auxiliary reflective element may have one of (a) a glass substrate having a surface coated with a metallic reflector coating and (b) a polymeric substrate having a thin glass element applied to a surface thereof and with an opposing surface thereof having a reflecting layer applied thereto.