Leinster suffered a surprise Pro14 defeat against Ospreys on Saturday, while Cardiff Blues won for a fifth game in a row.
Following on from Rory Best's contract extension, Rob Kearney has agreed a deal with the IRFU until November 2019.
After almost a year out of action due to a back injury, Leinster and Ireland's Jamie Heaslip has been forced to call it quits.
Rob Harley's record 178th appearance for Glasgow Warriors was one to forget as they were beaten by Munster.