During the NXT Takeover R Evolution Pre-Show NXT Superstar Corey Graves announced that he would be retiring from in ring competition due to several concussions. He then announced that he would be joining the NXT announce team.

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http://www.wwe.com/shows/wwenxt/nxt-takeover-r-evolution-2014-12-11/corey-graves-retires-joins-nxt-announce-team-26899471