Sylvia, who is set to face his old club for the first time, remains a popular figure at Melbourne but old allegiances seem to have been put aside, at least until the final siren.
On Friday, Freo assistant coach Michael Prior said "the trap" for Sylvia might have been trying to catch up with his former teammates in Darwin before the match, which made sense to Grimes.
"That might be the answer," Grimes told AFL.com.au. "I'm not sure if a couple of the other boys have caught up with him or said much to him.
"He was a really well-liked guy down here and he was obviously here for a long time so he made some pretty good friends.
"He's a great guy, Col, so I'm sure after the game a few of us will be catching up with him.
"But like they (Prior) said he is a pretty social guy, too, so it's probably hard to hold him back at times.
"Obviously it's a big game for him, when anyone comes up against their old team it's a massive occasion for them – especially for someone like Col."
Sylvia played 157 games in 10 seasons at Melbourne, but had to wait until round 13 against Richmond at the MCG for his first game for the Dockers.
The 28-year-old has strung together three games since and Grimes knows how dangerous his former teammate can be when on song.
"When he's on, he's really on and he's pretty hard to stop," Grimes said.
"We know him very well and know a lot of things about his game, but he's a great athlete and he can do a lot of things so I think whoever's playing on him at the time has to stay alert as they can.
"He's one of those guys if you give him a look and give him a bit of a sniff and gets his confidence up he can really be a damaging player."
Sylvia aside, the Dockers have plenty of attacking weapons, not least small forward Hayden Ballantyne, who will play his 100th game in Darwin and could be favoured by the slippery conditions.
"He's probably a real barometer for them, we think. When he's up and going, the team seems to be up and going," Grimes said.
Saturday night's clash will be Melbourne's fifth game in Darwin (it has a 2-2 record) and the Demons announced a new deal on Friday that will see them call the Northern Territory home for two games each season in the next two years.
"We're hoping that this becomes our second home ... and really make it feel like a second home too," Grimes said.
"The support for us – I think that's one of the reasons we love coming up here – is because the support's been awesome.
"I'm really hoping we stay up here and keep the connection going."
