Rugby: From crunching tackles to numbers - how do the Magpies compare to the Premiership big guns?

Ash Dixon led his Magpies to Mitre 10 Cup Championship glory, but could they have pushed Tasman and Auckland in the Premiership? Photo / Paul Taylor

Just how good were the Hawke's Bay Magpies this season?

I shouldn't admit this, but even before last Friday's Mitre 10 Cup Championship final I was booking a fantasy grand final for them against whoever won the Premiership.

That's no disrespect to Northland either, who were strong early on in both of their matches in Napier this season before fading after halftime.

Hawke's Bay had just been so tough to beat at McLean Park all year that anything other than a coronation in front of our awesome home crowd seemed almost impossible.

The Magpies won nine of their 12 games this season, a tally equalled only by top-tier winners Tasman.

They scored 52 tries as a team in 2020, six more than any other province.

But across both competitions, how good were they exactly?

That's a hard question to answer given the uneven nature of the Mitre 10 Cup and its two divisions.

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Every team plays the other six teams in their own tier, plus four of the seven sides at the other level in crossover games.

That means unlike a typical round-robin, teams can have fixture lists of vastly differing strengths.

And the Magpies were a bigger beneficiary of that than anyone as the only team in New Zealand who didn't play either of the competition's two leading lights; Tasman and Auckland.

So how can we account for this in establishing how good they are?

A Simple Rating System (SRS), a piece of analysis commonly used in US team sports, rates teams by taking into account average point differential and the strength of playing schedules.

The number it produces represents the number of points by which a team is better or worse than an arbitrary average team for the competition.

Here are the Premiership and Championship tables as they stood at the end of the regular season:

And here is a combined table sorted by average margin of victory or defeat in every game, including semifinals and finals.

The Magpies jump right up, but because they played an easier schedule, we need to adjust for this by assigning a value representing the strength of each team's fixture list.

We shift the margin of victory figure up or down accordingly, feed the adjusted numbers back into the model and do so over and over again until they stop changing.

The final number gives us the score by which we can expect each province to either win by, or lose to, a mythical average Mitre 10 Cup side.

You might be wondering why this model says that North Harbour were the third best team in the country, even though they were relegated from the Premiership.

Taking a closer look at the top-tier table, Harbour finished just one win and two competition points outside of the semifinals.

The Simple Rating System looks kindly on their big wins over Tasman (40-24), Hawke's Bay (46-10) and Auckland (23-22), as well as an ability to get close in their losses as evidenced by three losing bonus points, second-highest in the competition.

Conversely, Premiership semifinalists Waikato and especially Bay of Plenty outperformed the model in the actual competition due to a consistent ability to win those close encounters, with three and four wins by less than seven points respectively.

Hawke's Bay were the fourth best side in the country this year, according to the Simple Rating System, just under an unconverted try worse than leaders Auckland and Tasman.

Crunching numbers is one thing.

With the Magpies joining the Premiership division next year, we will finally get an idea of how our boys stack up against the cream of the crop.