Gotch joined Port Adelaide in 2012 as the club's AFL assistant coach responsible for defence.
He served in that role for one season before moving home to Melbourne as the club's full time opposition analyst.
Port Adelaide's general manager of football Peter Rohde thanked Gotch for his contribution to the club.
"Gotchy has been a very popular and valuable member of our club for the last two years," Rohde told portadelaidefc.com.au.
"He was a great contributor as our defensive coach last year and this year as our opposition analyst.
"We thank Brad for his work with our club and wish him all the best with the Panthers next year."
