Brown bird, red breast - not a robin?!

Hi, there is a brown bird with a red breast visiting our garden that is bigger than a blackbird. It's not very defined and it's definitely not a robin. It digs around the ground, washes itself in the bird bath and always appears on its own. We've never seen it before and it's been visiting for the past few weeks. We're in Brighton, UK. Desperately trying to get a decent photo to share.... Anyone have any ideas? Thanks!