Key forward Tim Membrey left Sydney in 2014 for St Kilda, desperate to become an AFL regular after managing one game in two seasons.
At Etihad Stadium on Saturday, the Swans' defence will get an update on how much Membrey has developed since when the two teams clash.
The 22-year-old led the Saints' goal-kicking last year and is one of many potent threats that Swans fullback Heath Grundy and his colleagues are rightly wary of.
"I had a little bit to do with Timmy when he was up here, he's a great bloke and his career has really blossomed since he went to the Saints," Grundy said.
"He's become a really important player for them and a pretty handy forward. He's one we will have to watch.
"He works hard and gets to the right spots. He reads the play really well and has a good set of hands."
It begs the question of why the Swans let Membrey walk.
It wasn't a matter of money, the salary-cap squeeze created by Lance Franklin's arrival didn't influence either party.
Membrey was desperate to play at the highest level and realised his chances of doing so were much better at a team without so many gun forwards.
"We knew that Tim would be a pretty good player. We offered him a contract to stay but we couldn't guarantee him a game," Swans coach John Longmire said.
"He's pretty talented ... he's a ripping young bloke. We would have liked to keep him.
"Now he plays regular senior football and it's not a surprise to us. Good luck to him. We just hope he doesn't play well this week."
Grundy expects to spend time on Membrey and a handful of other Saints, such is the way St Kilda rotate players through their forward line.
The Swans' defence will be boosted by the return of 2016 All Australian Dane Rampe, who has the ability to play on both small and tall forwards.
Rampe has been sidelined for seven games with a broken arm, an injury caused when he tripped over a chain while running on the pavement outside the SCG.
The Swans have posted a 'please don't jump over chains, even low chains' sign at the club.
"He's copped a bit of flak about it," Grundy laughed
"It's a really unfortunate accident. You think of all the physical contact you have at training and in games, then he does it like that.
"He's quite loud and provides a lot of energy for the group. It's something we've missed."
