Collingwood's Dale Thomas has played against the Sydney Swans 10 times and never walked away a loser.

But Friday night's Preliminary Final at ANZ Stadium in Sydney is the most important contest Thomas has taken part in between the teams yet.

And once again he will be front and centre of the Swans' thoughts, as he could be the difference in a game that seems likely to be close - because Thomas can win a game in about the time it takes to make plunger coffee.

Like all the best burst players Thomas creates a football illusion.

The illusion is that such player's fortunes are dictated simply by their attitude in the moments before and after they tear a game apart.

'Daisy' Thomas busts that theory into little pieces.

He did little different in preparing for Saturday night's game against the Eagles than he had done the week before against Hawthorn.

And although he took confidence at half-time of the semi-final from his first half efforts, he had no special build-up to the second half.

Yet the outcome was different from one week to the next, and the response to his effort way, way, different.

"The week before I had a down game and I got asked a lot about it when realistically I had done nothing different," Thomas said.

Perhaps the increased impact was due to luck. 

In some ways, says Thomas, but he has been around long enough to know that luck is something you need to be ready to greet when it arrives.

"Where preparation meets opportunity is luck," Thomas said. "I take great belief from the fact that if I do prepare well, then … the harder you work the luckier you seem to become."

That's why Thomas is dangerous, because his effort continues regardless of whether the ball is bouncing his way or not.

In fact, to describe him as a burst player does him a disservice because he is much better than that, but he has shown several times this year he can turn it on and change a game in an instant.

Against Richmond in round two, he kicked two goals in the first four minutes after half-time, winning three contested possessions, two clearances and one inside 50 in the first 10 minutes of that third quarter.

Against Adelaide in round nine he broke the game open in the last quarter when it was a goal the difference, with five disposals, three contested possessions and one clearance in the first 10 minutes after three-quarter time. 

In the seven minutes that followed half-time against the Eagles he kicked three goals from three disposals and had the MCG rocking as Collingwood hit the lead.

He had entered half-time on Saturday night with a clear mind and a confident outlook.

"I thought in the first half that although I did not have a great deal of the ball I was in some pretty good spots at times where I was missed," Thomas said.

"That is footy. You know you are not going to get the ball every time."

He was happy with his work-rate, his pressure around the ball and his competitiveness so he knew from experience his fortunes would eventually change.

"It is only a matter of time when you are doing those things that you get hands on the footy and have an impact," Thomas said.

Diligent and tough, the classic wingman works with the ball and without it.

His tackle in the first seconds to slow Nic Naitanui was the perfect example of the mindset he took into the game.

His effort to chase Will Schofield in the third quarter was a sign of how relentless those who play winning football need to be.

Thomas knows the truth, as every sportsperson does, that it's easier to talk the mind into running full tilt when an attacking opportunity presents itself than it is to put the foot down when the goals might need to be guarded, however Thomas never stops working both ways to either attack and defend.

It's part of what endears him to coaches and teammates alike.

But supporters love goals and the second of his three after half-time was Thomas at his best.

He hunted the ball from the wing like a greyhound chases a lure, taking the bend at speed with his sights set on the prize. When the ball bounced his way he had the skill (and fitness) to gather and snap the goal.

To pounce and snap was his preferred build up too, as he has kicked 22.12 this season in total (64.7 per cent accuracy) with just 7.9 (43.8 per cent) coming from set shots.

If there is a weakness in his game that might be it, but it never stops him wanting the ball in his hands when the moment demands it, as it did soon after half-time when he kicked straight from 30m to get the Magpies rolling.

As exciting as it was to watch, Thomas knew how to manage the moment.

"Honestly, you don't have an awareness of the whole crowd," Thomas said. "It's just the boys. That's probably the biggest thing when there are a few high fives on the way back but you move on from that to the next contest."

Now he moves on to his fourth Preliminary Final in as many seasons.

This is the biggest test yet, and Thomas will be working as hard as ever to make the ball bounce his way.

Stats supplied by Champion Data.