Identify please, small bird

Hi there, not posted on here before, I am not a birder, but normally do not have any trouble identifying garden (and other) British birds but am perplexed trying to identify this small bird that arrived in the garden yesterday and spent a couple of hours with us. Location is suburban West Midlands with countryside 1/2 mile west. The bird was slightly larger than a robin, robin-like behaviour (without the bobbing), brown to dark brown upper and pale dusky pink fading to off-white on breast/underside, thin 'insect' beak similar to Robin, distinguishing features are horizontal dark flash across the eye (not very prominent though) and a white splash above the tail - noticeable only in flight. I am quite good identifying birds and this one has not something I've seen before. It looked a little confused by it's surroundings but was not all that timid, it perched on walls and posts with a wagtail-like flick of its tail occasionally, and one-time jumped after insects/flys like a Flycatcher would. I got a couple of pictures but can't see how to post them in this thread. Anyone got suggestions? It's got me puzzled!