The 22-year-old Ice Blacks forward took a blow to his right shoulder early in his side's 8-3 loss to the Botany Swarm at the Dunedin Ice Stadium last Saturday and requires season-ending surgery.
''I just went to clear the puck,'' he said.
''I dived to reach at it, slid into the board and kind of tried to take it on the shoulder. But I ended up dislocating it and chipping a bit of bone off the joint on the way out.''
Harrison has a history of shoulder injuries.
He had his left shoulder reconstructed five years ago after picking up the same injury as he did a week ago, and has also torn his AC joint in his right shoulder in the past.
While Harrison, a design and computer science student at the University of Otago, is disappointed his season ended so early, he is now looking forward to getting on with the operation and recovery.
He is still waiting to find out just when his right shoulder will be operated on, but expects the recovery process to take about two months.
''Five minutes into the first game of the season is never good,'' Harrison said.
''I've just got to get back to it. Get on with surgery, start recovering and look forward to next season, I guess.''
While he is not particularly good at being a spectator, Harrison intends to support his team in its bid to go one better than the past two seasons, when it finished second behind the Canterbury Red Devils.
Harrison, who is from Arrowtown and played for the Southern Stampede before moving to Dunedin a couple of years ago, watched the Thunder bounce back from Saturday's loss with a 6-4 win over the Swarm on Sunday.
There is no doubt the Thunder will miss Harrison's attacking prowess this season, but debutant American import Austin Konchar stepped up in his place on Sunday by scoring three goals.
Harrison said he will ''definitely'' be back to play for the Thunder next season.
The Thunder plays the West Auckland Admirals in Auckland today and tomorrow.
