
1) NBA Sixth Man Award winner 2) Not your average sub sandwich 3) The ultimate luxury sandwich 
Found on 
https://www.crosswordclues.com/clue/supersub

Under experimental One-Day International rules introduced in July 2005, the twelfth man became a substitute, able to come on and replace any player, with the substitute able to take over the substituted player's batting and bowling duties. A twelfth man used as a substitute in this way was known as the supersub. The first supersub was Vikram Solank...
Found on 
http://cricker.com/glossary/

Under experimental One-Day International rules introduced in July 2005, the twelfth man became a substitute, able to come on and replace any player, with the substitute able to take over the substituted player's batting and bowling duties. A twelfth man used as a substitute in this way was known as the supersub. The first supersub was Vikram Solank...
Found on 
http://en.wikipedia.org/wiki/Glossary_of_cricket_terms

A short-lived experminent in 2005 by the ICC to try to spruce up one-day internationals. It allowed teams to replace on player during a game, but the reality was it heavily favoured the side batting first and was quickly dropped.
Found on 
http://www.espncricinfo.com/ci/content/story/239756.html
  No exact match found.