A paddle-wielding robot is so adept at playing table tennis that it is posing a tough challenge to elite human players and sometimes defeating them, according to a new study in the journal Nature that shows how advances in artificial intelligence are making robots more agile.

A humanoid robot runs among human participants during a half marathon event in Beijing, captured by staff photographer Han Guan Ng. The image shows the alignment of runners, robots and event staging in a single frame.