Grigg did not play an AFL game in 2012, instead playing for the Norwood senior and reserves sides in the SANFL.[2] He made his debut late the next season, in round 17 against Geelong, after showing strong form in the SANFL.[3] In five games in 2013, he averaged an impressive 16 possessions, returning to Norwood for the finals where he helped them to a premiership.[2] He also re-signed with the club for two years.[4]
Grigg struggled to break into the side in 2014 and 2015, hampered by the substitute rule and untimely injuries, but he performed well in the SANFL for Adelaide's new reserves side, polling the most Magarey Medal votes for the club in both seasons.[2] At the conclusion of the 2016 season, he was delisted by Adelaide without an AFL game being played for the 2016 AFL Season. After he was delisted by the Crows, he returned to the Norwood in the SANFL, the club he played for prior to being drafted by the Adelaide Football Club.[5]