THE BUILD-UP to the blockbuster first preliminary final between Collingwood and Geelong started with Mark Thompson's reference to the Collingwood jealousy and hatred of Geelong and the need for his team to hate the Magpies just as much in return.

A media with an insatiable appetite for content immediately - and I think inaccurately - described his words as mind games. In my experience, coaches get asked questions at press conferences and answers are reported as statements. Rarely are they directed towards the opposition.

I suspect what Mark Thompson may have been doing last Friday night when he invoked the word 'hatred', was a bit of thinking aloud about the mindset he wants his players to adopt in Friday night's match.

In the back of his mind would have been the round 19 clash between the two sides when the Pies beat the Cats by 2.10, or 12 more scoring shots. A win much more convincing than the 22-point margin might suggest.

The most telling stats in that game were Collingwood's 144 to 104 contested possessions and 45 to 29 domination of the clearances. No doubt a repeat of these numbers will deny Geelong a fourth consecutive grand final.

With his post-game comments, Thompson had inadvertently identified the Geelong coaching theme that will be pushed behind closed doors in the build-up to the game.

So while 'hatred' is a very strong word, when he spoke of this sort of thing what he was really doing was conveying the message he will be giving to his players this week. Or more particularly, creating the highly-aggressive emotional state that leads to the sort of desperate footy that the Cats must produce to win.

Thompson will be trying to make sure that Geelong attack both the footy and the Collingwood player in possession with an energy and fanaticism that exceeds the physical attack that their players received from the Magpies in round 19, or can summon up this week.

They will need plenty of Joel Selwood-type kamikaze attack on the contest because Collingwood have been consistently brilliant in this part of the game.

The clearances are where the ball-winning contests start 80-odd times a game.

So, while clearances and ruck hit-outs generally have a minimal correlation at best, the issue of ruck control definitely has a huge impact.

That's why the ruck contests shape as such an important aspect of the game and will underpin one of the really intriguing selection decisions that Geelong must make.

For me, Darren Jolly has been the recruit of the year. He's taken the Collingwood ruck division from a vulnerable mediocre unit to one with an experienced top-notcher.

He is a strong, highly-resilient big man who plays on average 80 per cent of game time. And he rarely seems to get injured, as evidenced by the fact he's played all 23 games this year.

His enormous contribution means the Pies are more than well-served by having the versatile Leigh Brown do the other 20 per cent of the ruck work.

The big selection intrigue, then, is whether Geelong go with Mark Blake, the specialist ruckman or Tom Hawkins, the better ball-getter who isn't great in the hit out department as the support to Brad Ottens.

Ottens, like Jolly, is a very talented big man but he doesn't have the same physical resilience or the ability to ruck for as long. He has only played 14 of a possible 24 games and has averaged only 63 per cent of time on the field.

This means, effectively, that the Geelong back-up ruckman is required to do around 40 per cent of the ruck work.

I never try to pre-empt club selection as an outsider because we never know all the relevant information.

Having said that, I'm inclined to think it might be worthwhile for the Cats to play another specialist ruckman in Blake in preference to Hawkins, in an effort to blunt the ruck influence of Jolly and consequently be more competitive in the all-important clearances.

One of the reasons why clearances are so important against the Cats is because if the opposition gets on top in the ball-winning department in the back half and midfield, then it tests the questionable chasing ability of the Cats onballers, particularly against the Magpies' hard-running spread into space.

In round 19 the Pies had a very high 66 forward 50 entries for a score of 14.23. Or more importantly, 37 scoring shots. Clearly, the Jolly influence and the clearance domination were key factors.

Whenever I watch Collingwood play, what really strikes me is their enormous energy levels. Their use of the interchange bench gives them an incredible physical freshness and, most importantly, it creates a really strong psychology.

The fleet of Magpie running players have adjusted their entire mentality to play the game in small bursts. They go as hard as they can for seven or eight minutes, go off for a few, and then return for their next short burst.

They are giving more of themselves physically because they have no fear of getting tired.

As much as I almost bite my lip in saying this, given that I've not tipped against Geelong in about three years, I'm going for a Collingwood victory this week.

I do that despite my vivid memories of Geelong's 101-point demolition of the Bulldogs in round 20, when the Cats were coming off their loss to Collingwood.

It was one of the most amazing performances I've seen, and while I still think they've got an upper level that nobody can match, the Cats will find it hard to produce it against the swarming pressure game of the Pies.

Right now the Cats just don't seem to have that same invincible look as often as they had a year or two ago.

The views in this article are those of the author and not necessarily those of the clubs or the AFL.

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