Just how important is a good start to the season?

Yes, a good start to any football season is obvious if a team wants to do well.

However, with the usual concerns by supporters of various clubs after the first round of 2021, likely to continue next week given my own concern that Essendon has a tough four weeks coming up, I was interested to know how important a good start is to a season in statistical terms.

In other words, can a team still do well after losing their first two or three games?

I know it is possible.

In 1975, Essendon were undefeated after four rounds, after defeating the previously undefeated Carlton in front of 77,000 people at Waverly on Anzac Day, yet did not make the finals. Yet, North Melbourne that year, after losing their first four matches, went on to win the premiership.

I have selected five rounds as a measure of a good or poor start to a season. So, what happened to the 52 teams, since 1970, that did win their first five games?

While there have been 34 seasons during the past 51 years where there has been at least one undefeated team after Round 5, only 13 went on to win the premiership: Hawthorn in 1971, 1976 and 2008, Carlton in 1979, 1981 and 1995, Geelong in 2009 and 2011, North Melbourne in 1977, Essendon in 2000, West Coast in 2006, Sydney in 2012 and Richmond in 2017.

Another 13 sides undefeated after Round 5 have made the grand final (giving us 26 in total making the decider), but lost: Collingwood in 1970, 1981 and 2011, Carlton in 1973, Hawthorn in 1975 and 1984, North Melbourne in 1978, Melbourne in 1988, West Coast in 1991 and 2005, Geelong in 2008, St Kilda in 2009 and Adelaide in 2017.

This gives us 26 of 52 undefeated teams going on to make the grand final, with 13 of that group winning it. Hence, if a team is undefeated after five rounds, the 1970-2020 data suggests around a 50 per cent chance of making the grand final and 25 per cent of winning the premiership.

Of the 52 undefeated teams after Round 5, only four did not make the finals: Melbourne in 1971, who finished seventh (only the top four made finals that year), Geelong in 1999, who finished 11th, Collingwood in 2000, who finished 15th after winning only two more games, and Essendon in 2013, who were banned from playing finals due to the doping scandal.

While I do not have the time to research the 51 seasons with other win-loss records, say 5-0, 4-1 or any other, the above data shows all is not lost if you only win a few games, albeit the odds of doing so are reduced the fewer wins a team has by Round 5.

Of the 102 grand final teams since 1971, 31 teams had four matches (or four and draw) of the first five games winning 20 premierships. In other words, of the 51 grand final winners since 1970, 33 had won at least four games after five rounds.

Of the 102 teams that made the grand final, 57 won at least four games.

Of the 24 teams who made the grand final winning three matches (or three matches plus a draw), eight won the premiership.

Of the 19 grand finalists who won two matches (or two matches and a draw), eight won the premiership.

Of the four teams who won just one match (or one match and a draw), only two won the grand final (North Melbourne 1975 and Essendon 1993).

No team has made the grand final since 1970 losing all of their first five matches.

I hope Essendon has a few wins on the board by Round 5, but it will tough given its next four matches (Port Adelaide away, St Kilda home, Sydney away and Brisbane away). I live in hope.

All stats above sourced from AFL tables