Chaplin, 23, has played 73 games with Port Adelaide since debuting in 2004.
Chaplin was drafted with pick 15 in the 2003 National Draft, from North Ballarat in Victoria’s under 18 TAC Cup competition.
Port Adelaide’s General Manager of Football Operations Peter Rohde says the club is pleased to have re-secured Chaplin’s signature.
“We see Troy as an important part of our long term future, it’s great to have him secured,” Rohde said.
“With him and Carlile both signed up, we’ve got two key defenders to build our backline around long term.
“He’s still got some areas to improve on, but he’s shown great work ethic and we’re looking forward to him continuing his improvement here at Port Adelaide.
“Troy brings great character to the club and is an important part of the culture amongst our younger players here at the Power.”
Chaplin says he’s now settled here in Adelaide with his fiancée Lisa and is excited about the direction of the list.
“It’s great to be staying here at Alberton for another three years,” Chaplin said.
“We’ve got an exciting list and I think we’re improving as a team and the group is moving forward. We’ve shown that our best is pretty good and now it’s just about working on that consistency. It was a pretty easy decision in the end.
“It’s been a great six years so far, and hopefully the next three are just as good with more success along the way.”
