You never know what might happen when Hawthorn and Geelong meet. It can truly be said of this pair that they have history, both modern and ancient. There's been infamy, like Matthews and Bruns in 1985, and grandeur, such as the '89 grand final epic. Earlier that year, also, there was one of history's greatest comebacks: Hawthorn back from 56 points down to win by eight.

It's their recent rivalry, though, that is of football's purest kind and which outstrips those earlier events. This has become a struggle, fought out over seasons, between two clubs truly vying for ultimate supremacy. It's been the best contest in the contemporary game and one that requires no false hype. These are, after all, the teams that have won the last three flags.

Even through the period of Geelong's domination of the competition, over three-and-a-half seasons, they've not managed a clear-cut win over the Hawks. They've battered every other team - at least once - by 10 goals or more, but not Hawthorn. The Cats have won four of their six encounters since the start of '07, but with a biggest winning margin of 11 points. Modern scoring machine that it is, Geelong has averaged below 13 goals per game and hasn't managed more than 15 in any of those six matches. When it really counted, in the 2008 grand final, the Hawks prevailed. In the two most recent encounters, Geelong has had to come from behind at the last change to win. Against the Hawks, the Cats have been fallible.

On Saturday afternoon at the MCG they'll face off again. The stakes are high, as always. Hawthorn has won seven straight games but still hasn't redeemed its disastrous start to the season. The Hawks simply have to keep winning to retain any hope of making the top four. While Geelong's remarkable consistency insulates it from that sort of struggle, a loss on Saturday is likely to demote the Cats to third place, an indignity they haven't experienced into the second half of a season since 2006.

The Cats, as has been the case in every game they've played since the middle of 2007, will again be the hunted. They are the benchmark. Early indications are they will start a reasonably firm favourite. Yet when you measure the teams against those that took the field on 27 September 2008, it's not easy to see why.

Geelong will be missing Mooney, Johnson, Rooke, Harley, and - unless they hurry them back from injury - Taylor and Ottens. That's their two major suppliers of goals through the great years, a major slice of their defence, and their best ruckman. The one significant "in" is James Podsiadly.

The Hawks have lost Sam Mitchell temporarily, and Shane Crawford, Stewart Dew, Mark Williams, Robert Campbell and Trent Croad permanently from the team that won the '08 flag. On the credit side are Shaun Burgoyne, Ben Stratton, and Carl Peterson among others. Were it a mathematical calculation, Hawthorn would be red-hot favourites.

It's not, though, and Geelong desperately wants to beat Hawthorn. Its coach, Mark Thompson, has admitted the pain of that hot September day in '08 will never go away for his players. In round 17 last year, a weakened Geelong came back from 28 points behind the Hawks early in the last quarter for a thrilling one-point win. The Cats were as excited as we'd seen them all year, having driven a stake through the finals chances of their great rival. This time, the rival is playing better than it was back then, the Cats are more depleted, and the task looms large. The Hawks would love to give that mat under Geelong another tug.

Clashes between these two teams might historically be full of surprises, but we can look forward to Saturday confident that it will bring another fierce contest. While it won't tell us all we'd like to know about the combatants' chances in 2010, it's nice to keep a few secrets for later.