Laura Muir: World and Olympic crowns are now within her reach

Some superstars propel themselves into the limelight like a wrecking ball from a cannon. Others light a fuse but make us settle back for a slow burn. In life, as on the athletics track, Laura Muir has never been one to loudly demand attention. Her deeds can generate noise enough. And although the Scot was once more prospect than prodigy, she now resembles a human torpedo on a trajectory into the unknown.