John Smit ended his playing career as a flyhalf.
Wales international scrumhalf Tavis Knoyle is to join Gloucester from Scarlets on a two-year deal.
Former England wing Tom Voyce has decided to hang up his boots at the age of 32.
Scotland and London Irish centre Joe Ansbro announced his retirement, after losing his battle to recover from a broken neck.
John Smit will captain Saracens, in what will be his farewell appearance, against the SA Barbarians on Thursday.
Saints Director of Rugby Jim Mallinder admitted his side had never lost self-belief as they finally ended their Premiership play-off hoodoo.
A fast start and a gutsy finish ensured Saints upset table toppers Saracens 27-13 in their play-off clash and secured a spot in the Premiership Final.
Leicester Tigers Director of Rugby Richard Cockerill lavished praise on his team after they booked a ninth straight Premiership Final.
Leicester Tigers booked a place in their ninth consecutive Premiership Final with a 33-16 victory over Harlequins on Saturday.
This is Saracens fourth successive Premiership semifinal and their fifth overall, however they have lost their last three semifinal encounters in all competitions.