Lonergan played in the Geelong team in the 2008 AFL Grand Final, and missed selection into the Geelong 2009 premiership team.
 However, during 2011 Tom became a key member of Geelong's defensive back six players, and played a critical role in the 2011 AFL Grand Final holding Travis Cloke goalless in the second half, after Cloke had kicked three goals early in the game while playing on Harry Taylor.
The job he executed was crucial for the Cats as it helped stemmed the flow of Collingwood goals and took the red-hot Cloke out of the game.

During the 2014 AFL trade period, Lonergan was offered a three-year contract to join the Western Bulldogs, in a deal estimated to be worth $500,000 a season.
Lonergan, who was already contracted to Geelong for 2015, ultimately rejected the offer, citing loyalty to his teammates and the resignation of the Western Bulldogs' coach Brendan McCartney as his main reasons for remaining with the club.
He continued to play for Geelong through the 2016 and 2017 seasons.
Lonergan played the final game of his career in the 2017 Preliminary Final, where he collected 10 disposals in a heavy loss to Adelaide.
Lonergan played in the Geelong team in the 2008 AFL Grand Final, and missed selection into the Geelong 2009 premiership team.  However, during 2011 Tom became a key member of Geelong's defensive back six players, and played a critical role in the 2011 AFL Grand Final holding Travis Cloke goalless in the second half, after Cloke had kicked three goals early in the game while playing on Harry Taylor. The job he executed was crucial for the Cats as it helped stemmed the flow of Collingwood goals and took the red-hot Cloke out of the game.
During the 2014 AFL trade period, Lonergan was offered a three-year contract to join the Western Bulldogs, in a deal estimated to be worth $500,000 a season. Lonergan, who was already contracted to Geelong for 2015, ultimately rejected the offer, citing loyalty to his teammates and the resignation of the Western Bulldogs' coach Brendan McCartney as his main reasons for remaining with the club. He continued to play for Geelong through the 2016 and 2017 seasons. Lonergan played the final game of his career in the 2017 Preliminary Final, where he collected 10 disposals in a heavy loss to Adelaide.
Tom Lonergan (footballer)