23-year-old Trengove has played 91 games for Port Adelaide since debuting in 2010.
Senior Coach Ken Hinkley says Trengove is a great leader for the club.
“He’s an outstanding player but he’s also one of the elite leaders of our football club,” Hinkley told portadelaidefc.com.au.
“He’s not just significant on game day, he’s significant through the week, around the club and with the players in setting standards on what we expect of players who play for Port Adelaide.
“He’s one of those blokes who helps others get to the level they need to.”
Trengove has been at Port Adelaide since being selected at pick 22 in the 2008 National Draft.
He tied with Travis Boak for the John Cahill Medal as the club’s best and fairest player in 2011.
The key defender has played every game this year, despite suffering a knee injury in the pre-season.
“He was a long time out, about eight weeks and he came straight back in and played right from game one and his form has been first class as a key pillar in our back half,” Hinkley said.
“When you miss that much pre-season and you come in and have the season he’s had it’s a real credit to him.”