The Saints will announce on Tuesday a three-year extension for the West Australian, who played three senior matches in his rookie year. He made his debut against Hawthorn in round seven and retained his spot for another fortnight. He finished the season with a quad injury.

Having already had senior WAFL experience, Acres was taken as the 19th overall selection in last year's national draft.

He follows Luke Dunstan, Josh Saunders, Jack Newnes, Lewis Pierce, Nathan Wright and Jimmy Webster - the latter re-signed on Monday - to show faith in the rebuilding club.

"It's a great time to be at St Kilda. We, obviously, have a young group coming through and to sign on until the end of 2017 feels really good," Webster said.

"There is a great vibe amongst the young guys at the club at the moment. On the field, we are hard on each other but also support each other. Off the field, we are really good mates and enjoy each other's company."

Webster's season ended with a foot injury in round 15 but he is expected to be recover in time for the start of pre-season training.

"I need to get my foot right in the off-season, get my fitness up, work hard in the gym and prepare as well as I can for 2015," he said.

"I have no doubt that we can climb back up the ladder sooner rather than later as the young players continue to develop and learn."