The Boks could have used a player of Pienaar's experience and versatility on tour to Europe, and at the Rugby World Cup in Japan next year, but he says that chapter of his career is now firmly closed.
Deysel, who joined Ulster from Guinness Pro14 rivals Munster in 2017, made his decision because of a "combination of lower-body injuries and various niggles".
Former Wallaby Henry Speight scored a try in a dramatic finish to ensure a draw for Ulster in their PRO14 encounter against the Cheetahs in Bloemfontein on Friday.
Former Springbok loose-forward Marcell Coetzee rock the shackles with a second-half try to help Irish side Ulster to a 28-7 victory over hosts the Southern Kings in their PRO14
Ireland captain Rory Best insists big one-off performances that are not backed up, are no longer good enough for Joe Schmidt's side on the eve of their rematch with New Zealand.
All the reaction from around the European Champions Cup Round 2 as Toulon got back to winning ways and Munster remembered Anthony Foley.
- ULST7thTries Scored 1st Leinster : 27 Tries ScoredLEINS1st1827
- ULST10thPoints Difference 1st Leinster : 116 Points DifferenceLEINS1st3116