Harlequins and England centre Jordan Turner-Hall has been forced to retire from rugby at the age of 27 due to injury.
Aviva Premiership champions Saracens will open the defence of their title at home to the Sale Sharks on October 17.
England captain Chris Robshaw insists being World Cup hosts is a huge advantage.
Harlequins and England centre Jordan Turner-Hall has been charged with GBH following a nightclub incident in October.
European Challenge Cup holders Gloucester will face local rivals Worcester Warriors in the 2015-16 competition.
England full-back Mike Brown will be eased back into training after recovering from concussion.
Jamie Roberts is looking forward to next season with club and country after his move to Harlequins was confirmed.
Yorkshire Carnegie have announced the signing of Harlequins centre Tom Casson on a two-year deal.
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