Elevated from the rookie list, Phillips emerged as one of the surprise packets of GWS' debut season in 2012, making nine senior appearances over the back half of the year.
But repeated hamstring issues kept the Tasmanian on the sidelines for the entire 2013 campaign.
Now fully fit and with a string of strong performances in the NEAFL under his belt, coupled with Shane Mumford's continuing recovery from a knee injury, the 22-year-old will be thrown back into the fray at Patersons Stadium.
"It's a great story," GWS coach Leon Cameron said. "Andrew hasn't played since 2012.
"His last four weeks in the NEAFL have been terrific; he's really put his hand up and we look forward to seeing him on Sunday.
"It also gives Jon (Giles) a chance to play more forward. Having two genuine ruckmen coming into this game is important."
Sunday will also mark a special occasion for Giles, who will become the first Giant to reach the 50-game milestone.
Giles has played in all but two games in the club's short history, including the last 36 in succession.
The 26-year-old spent four years on Port Adelaide's list without playing a senior game before being delisted, but refused to let his AFL dream die.
He picked up a best and fairest award with SANFL club Sturt in 2010 before being given another chance by GWS via the 2011 Rookie Draft.
He's been part of the Giants from day one, competing in the NEAFL in their first season prior to joining the AFL, and will beat GWS co-captain Callan Ward to the milestone by one game.
"You always have those doubts and getting delisted is a pretty hard thing to swallow," Giles said.
"But I was fortunate enough to get a second chance by the Giants.
"I'm part of an exciting group that's working really hard to get better and achieve great things."
Mumford started the season in outstanding form, helping the Giants to victories in two of their opening three games before his knee issue struck.
When he experienced swelling just before the round four clash with the Western Bulldogs, the club was concerned about a possible infection, leading to Mumford immediately going under the knife.
He took part in a reasonably intense training session with GWS physio Tim Parham on Thursday, including some 100m sprints at top pace and weight-bearing drills to test the knee out.
But with the Giants having a bye after the trip to Perth, the decision was made to give Mumford some further rest and reward Phillips for his consistent form in the seconds.
"He's 98.8 per cent right," Cameron said of Mumford.
"He did the warm-up today, he did some running, he's pulling up really, really well, but we've just erred on the side of caution just before we have a break.
"We'd love to play him alongside Jon this weekend, but it gives a great opportunity to Andrew Phillips to take up that ruck role."
The Giants will make a number of changes to face the Eagles, with Josh Hunt, Lachie Whitfield and Aidan Corr all joining Phillips in the team.
Jeremy Cameron misses out as he can't fly following a procedure on his eardrum, while Adam Treloar and Curtly Hampton both miss due to ankle problems.
The coach is expecting a stern test from a West Coast side that has played some decent football in recent weeks, but paid for poor kicking in front of goal in defeats to Carlton and Fremantle.
Giles also knows what to expect at Patersons Stadium.
"It's a huge task taking on Cox and Naitanui," he said.
"Cox has been such a great ruckman for so many years and Naitanui is such an exciting player and an impact player.
"It's going to be a great challenge for Sauce (Phillips) and myself."
Twitter: @AFL_JD