Since joining the club with the 51st pick in the 2007 Rookie Draft, Geary has played 161 games for St Kilda, and is coming towards the end of his first season as captain of the club.
Geary said he was pleased to extend his future, and believes he can have a big impact in helping develop the side into a consistent finals team over the next few years.
“We have shown at different stages this season that our best stacks up against any side but we haven’t been able to produce the level of consistency that we are working so hard to achieve,” Geary told saints.com.au.
“No one is content with the position we find ourselves in and we are desperate to finish the year off strongly.”
“It’s been an unpredictable season to date and all we can do is get to work this week and perform strongly in our remaining games.”
“I see a huge amount of upside in this group and I’m thrilled to be extending my contract by a further year to contribute to our continued development.”
St Kilda Chief Operating Officer Ameet Bains said he was thrilled to keep Geary around, and said he is a true leader around the club.
“Jarryn has been an important leader at the club for many years but has really grown in the captaincy role this year,” Bains told the club’s website.
“He is enormously respected by his teammates and coaches alike for his selfless attitude, and someone who really sets the benchmark for professionalism on and off the field.
“He has continued to perform at a really high level this season and is an integral part of our defensive unit. We are really pleased to have secured his services until the end of 2019.”