The Carlton midfielder has been up and down this year but has started to settle in recent weeks, a trend carefully monitored by the Magpies' forward scouts.
Buckley said Thomas wouldn't be treated any differently on Friday night but backed the ex-Pie to make a statement.
"There's no doubt that if you're in Dale's shoes, it's a marquee event," Buckley said.
"He represented this club for a long period of time, he's taken the opportunity to move on to a new club and that test happens for any player that moves clubs.
"I can't speak for him but he'd be keen to play well. But I don't see it any differently to any of the other 21 players who are going to be on the field."
The Pies will have to decide who Brent Macaffer plays on, with captain Marc Murphy in a rich vein of form and Bryce Gibbs solid against West Coast on Saturday.
They've looked closely at Thomas recently and have a detailed dossier on how his form has been building since a quiet start to the season.
"In our opposition reviews, his run is increasing, he's being played in multiple roles, whether it's down back or up forward or through the wing, he's been flicked around a bit," Buckley said.
"He's been playing around 80 per cent game time, rotating a lot...we can't control much of that but he's one of many we'll have to keep our eye on."
Buckley said it was hard to know how the Magpie Army would receive Thomas, but reasoned his free agency departure came under the same rules that gave Collingwood the likes of Quinten Lynch and Clinton Young.
"(Free agency) is a reality and we've got to understand that but the other fact is as soon as you're on the other side of the fence, you're the enemy," he said.
Young (corked thigh) looks set to face the Blues after training on Wednesday but Alex Fasolo is likely to miss with a sore right foot.
The classy forward missed last season after breaking his navicular bone in the same foot, but post-match assessment of the area during the week revealed no further stress damage.
Buckley said Fasolo had been carrying a sore toe in his left foot and compensating for it, which led to the soreness in his right.
The coach also said Nathan Brown and Marley Williams would come into consideration to replace Fasolo, who has been playing in defence this year.
Brown has played two VFL games after a shoulder injury and would be handy against the in-form Lachie Henderson or Jarrad Waite.
Williams returned in the VFL last weekend after escaping a jail term for his grievous bodily harm conviction and was physically "targeted" by Essendon's players, to which he responded well.
Buckley also said he believed Williams – who received a 12-month suspended sentence in a Perth court - would be able to deal with physical and verbal pressure if he was to play this week.
"He's a physical player and maintained his physicality without taking a backwards step but maintained his focus on the game," he said.
"That was really encouraging for us and physically he's up and about."
Coach @ncb_cfc has just finished his weekly chat with the media in the Westpac Lounge #gopies pic.twitter.com/dvX7eTEQM5
— Collingwood FC (@CollingwoodFC) April 30, 2014