YOUNG defender Harris Andrews has signed a contract that will tie him to the Brisbane Lions until the end of 2021.

Andrews, 20, was already contracted until the end of next season and has extended his deal for a further three years.

Midfielder Ben Keays and untried defender Sam Skinner have both recommitted until the end of 2019.

Andrews, taken with pick No.61 in the 2014 NAB AFL Draft, has played 47 games and is already in the Lions' leadership group.

He has been the mainstay of the Lions' defence this season, taking over from the retired Daniel Merrett at full-back.

"The direction the club is heading in really excites me. There was no doubt I was going to stay here," Andrews said on Tuesday afternoon.

"We're all on the same lines of understanding where the club is going and the direction it's taking. It's a very exciting time for all the young boys.

"Due to our young group, we're all just enjoying being up here. It's a real opportunity for us to grow as a group."

Lions' general manager of football David Noble said Andrews' signature was important.

"As a Queenslander he is a great reflection of our commitment to drafting and retaining local talent," Noble said.

"Harris will continue to grow as a leader of this club and is a big part of our future."

Andrews and Keays are both graduates of the Lions Academy.

Keays has played 23 games since his debut against the Sydney Swans last season, while second-year player Skinner has just recovered from his second ACL injury.