Munster captain Peter O’Mahony, an injury doubt for Sunday’s Champions Cup clash with Castres, says he and his squad will stand by Gerbrandt Grobler, as the debate continues over the decision to sign a player who served a two-year doping ban.

New Munster head coach Johann van Graan has pledged to do everything he can to persuade Peter O'Mahony his future lies in his native province, despite reports linking the club captain with a move away from Ireland.