Portland’s first two senior grade premierships were both achieved in A4 Grade/Division Four, which was the level at which the club commenced its South Australian Amateur Football League involvement in 1997. After narrowly failing to qualify for the finals on debut the Thunder went on to finish third in both 1998 and 1999 before claiming their breakthrough premiership in 2000 thanks to an 8.14 (62) to 4.11 (35) grand final defeat of Payneham NU. Between 2001 and 2005 Portland competed in Division Three, never finishing higher than mid-table, and eventually succumbing to relegation as recipients of the wooden spoon.
The Thunder’s second senior A4 Grade flag was captured in 2008 courtesy of a 10.9 (69) to 5.14 (44) grand final victory over Mitcham. This was followed a year later by a season of consolidation in Division Three during which the side managed 6 wins from 18 minor round matches to finish seventh of ten teams. In 2010 the Thunder reached the Division Three finals and were ultimately placed third. A year later they went better, qualifying for a grand final clash with Flinders Park and obtaining promotion as runners-up after losing by 43 points.
Portland adapted well to life in Division Two, reaching the finals in their debut season and ending up in fourth place. A year later they qualified for the grand final and went on to earn the third senior grade premiership in their history thanks to a 15.16 (106) to 12.7 (79) grand final defeat of Port District.
The Thunder performed solidly in Division One in 2014 and ultimately finished seventh. A year later, however, they struggled, winning just 2 matches en route to a wooden spoon and a ticket back to Division Two, This was followed in 2016 by the further indignity of a second successive relegation meaning that the Thunder were consigned to playing Division Three football in 2017, a season which saw them performing inconsistently to finish seventh of ten teams before dropping to eighth in 2018.
John Devaney - Full Points Publications