ST KILDA has re-signed ruckmen Billy Longer and Lewis Pierce on two-year deals, tying the pair to the club until the end of 2018.

Longer is yet to play a senior game in an injury-interrupted 2016, and the Saints' No.1 ruck spot that was largely his last season has been claimed by Tom Hickey. 

The 23-year-old could have been tempted to test the trade market at the end of this season, when he was due to come out of contract, with a number of rival clubs keen to bolster their ruck divisions.

But as forecast by AFL.com.au earlier this month, the former Brisbane Lion has chosen to stick with the Saints.

Pierce played his only senior game earlier this season, against Carlton in round 12.

Longer's 2016 pre-season was disrupted by a shoulder reconstruction he underwent last August, which delayed his start to contact training.

After returning to play VFL affiliate Sandringham's opening six games this year, he was sidelined for six weeks with concussion before resuming over the past two rounds.

The No.8 draft pick in 2011, Longer crossed to St Kilda in the 2013 trade period after playing nine games in two seasons at the Gabba.

The former Northern Knight played 34 games in his first two seasons at Seaford, including 18 of the Saints' first 19 games last year, before suffering his season-ending shoulder injury.

St Kilda's ruck division also includes American Jason Holmes, who is out of contract at the end of this season.

Holmes played all three of his senior games in the final three rounds of last season.