Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: The man who inflicted the injury that Arsene Wenger still regards as the starting point of Abou Diaby's injury woes says his tackle on the former Arsenal man still haunts him every day. Former Sunderland full back Dan Smith slid in on Gunners midfielder Diaby in a 3-0 defeat nine years ago in a challenge that fractured the Frenchman's ankle and ruptured ligaments. Arsenal boss Wenger went on to slam the then-19-year-old Smith and he is still feeling the reprecussions to this day. Diaby's time at the Emirates Stadium appears to have now finally come to an end with his contract expiring this summer but Smith still feels the impact of his victim's injury woes on the other side of the world.Ex-Sunderland defender Dan Smith is still blamed for Abou Diaby's injuriesHe says he is still haunted and reminded of incident that broke Diaby's legArsene Wenger hit out at Smith over the challenge nine years agoSmith says he thinks about it every day and that it affected his career 
 Question:He left _ shortly after the fateful challenge and subsequent spells at Aberdeen and St Johnstone didn't work out.

Sunderland