In a 2012 pre-season trial match, he tore the anterior cruciate ligament in his right knee,[6] ruling him out for the rest of the season, however the Storm decided to extend his contract for another year allowing him to come back from injury.[7]
In June, he re-signed with the Storm on a 1-year contract until the end of 2014.[10] He went on to play 11 NRL games in his debut season.[11]
2014
In March, Griffin re-signed with the Storm on a 2-year contract until the end of 2016.[12] In April during a New South Wales Cup game, he tore his anterior cruciate ligament for a second time, this time in his left knee,[6] stopping him from playing any NRL games in the 2014 season.[13] In July, he received a two match suspension from the NRL after being found to have placed a bet on NRL matches.[14]
2015
In April while playing in an Intrust Super Cup game for the Sunshine Coast Falcons, Griffin suffered a third anterior cruciate ligament injury, the second in his left knee, which would again rule him out for the season without playing any NRL matches.[6]
2016
After 1056 days since his last NRL match, Griffin returned to the Storm line-up in round 15 of the 2016 season, starting at hooker.[7][15] In October, he re-signed with the Storm on a 1-year contract until the end of 2017.[16]
2017
In 2017, Griffin was able to break into Melbourne's line-up more regularly, coming off the interchange bench in their 2017 NRL Grand Final win over the North Queensland Cowboys.[17] He finished the season having played in 14 NRL matches.[18] Two days after the grand final, he signed a 2-year contract with the Newcastle Knights starting in 2018, in a bid for more first-grade opportunity with AustraliancaptainCameron Smith ahead of him for the starting hooker position at the Storm.[19]
2018
In round 1 of the 2018 season, Griffin made his debut for the Knights in their 19-18 golden point extra-time win over the Manly Warringah Sea Eagles, scoring a try.[20] In June, he made his international debut for New Zealand against England in Denver, Colorado.[21] Just a week later, while playing for the Knights in their round 16 clash against the Canterbury-Bankstown Bulldogs, he was passing the ball from dummy half and his leg got caught in a position which ruptured multiple ligaments in his left knee, including a ruptured anterior cruciate ligament (ACL) knee graft, ruptured lateral ligament and torn lateral meniscus.[22] This would be his third ACL knee injury to his left knee and meant he faced a 9-12 month recovery period.[22]
2019
While working as a trainer and coach for the Knights during the 2019 season, Griffin ultimately didn't make it back from his knee injury, departing the club at the end of the season.[23]