Paddy Jackson will leave Perpignan after a single campaign in France, joining London Irish for their return to the Premiership.
James Haskell had looked to boost his Rugby World Cup chances at Northampton Saints but will now retire at the end of the season.
London Irish have boosted their squad ahead of their return to the Premiership, signing Australia prop Sekope Kepu.
Although their chances of reaching the play-offs were remote, Wasps still had hope until slumping in the second half at Bath on Sunday.
Having spent six successive years in the top flight, Newcastle Falcons were relegated from the Premiership on Saturday.
The race for the Premiership's last play-off space is hotting up and Harlequins put down their marker by beating Leicester Tigers.
Gloucester returned to the play-offs for the first time since 2011 despite losing to Worcester Warriors, who sealed Premiership safety.
Exeter Chiefs and Saracens kept winning at the top on Saturday, while Leicester Tigers' Premiership status is not yet secured.
With Ollie Devoto's try against Harlequins on Saturday, Exeter Chiefs crossed in a record 72nd consecutive Premiership match.
Anthony Watson was back in Premiership action on Friday, but Newcastle Falcons' time in the top flight looks to be coming to an end.
Jack Singleton, who came through Saracens' academy, is to return to Allianz Park next season on a three-year deal.
Anthony Watson has not played since the 2018 Six Nations but will finally return to the Bath team this weekend.
Lood de Jager is to leave the Bulls and join Premiership side Sale Sharks, where the South Africa lock has signed a three-year contract.
Perhaps unsurprisingly, the five nominees for the European Player of the Year all turn out for Champions Cup finalists Leinster or Saracens.
David Strettle will bring his rugby career to an end next month after 17 years as a professional.
England international Ben Te'o is one of eight players who will be leaving Sixways at the end of the Premiership season.