HOW old is too old to be head coach?

Never if you're talking about America's Major League Baseball.

The Florida Marlins has just appointed 80-year-old Jack McKeon, as interim coach for the remainder of this season. If that's a shock, try this: he's the second oldest head coach in history, behind Cornelius McGillicuddy (snr), not surprisingly known as 'Connie Mack'. Connie was 87 when he handed in his megaphone in 1950.

They certainly do things differently in the US, but check out these AFL comparisons with McKeon. The Marlins (admittedly interim) manager is older - by five years - than Ron Barassi. Older by six months than Tom Hafey. And just two years younger than the great John Kennedy.

McKeon's acceptance of the job is Kennedy's 'Don't think, do' in action, although it should be noted that he managed the Marlins to a World Series victory just eight years ago, at the age of just 73.

So, could we have an eighty-year-old singing the tune in the AFL?

We might have to wait until 2027 to find out. Imagine Kevin Sheedy (64 in December) re-appointed at the age of 80 to lift a struggling Essendon from the doldrums, after a worn-out 55-year-old James Hird hands back the keys.

The oldest coach we've seen was 'Checker' Hughes, who came out of retirement aged 71 years and 148 days to coach Melbourne for one game in round 13 1965 after Norm Smith was sacked then reinstated.

Jock McHale was 66 years and 266 days when he finished up his career coaching Collingwood in 1949. Only John Kennedy (aged 60 years and 249 days at North Melbourne in 1989) and Jack Worrall (aged 60 years and 40 days at Essendon in 1920) have also reached 60.

Sheedy will sit in the middle of that group of four legends when he coaches GWS next season, but he'll still be well behind the modern day marvel of world sport, Manchester United Manager, Alex Ferguson, who turns 70 at the end of this year. Often AFL people forget that when looking at coaching prospects, particularly when today's coach is more a manager of an executive of coaches, than the man who pulls ALL the strings.

American sports website ESPN released a list of venerable coaches in the wake of McKeon's appointment that included basketball legend Phil Jackson, 64, when he took the Los Angeles Lakers to the NBA title in 2010, Hubie Brown, 71, when he finished coaching the Memphis Grizzlies in the NBA 2004, the 63-year-old Dick Vermeil guiding the St Louis Rams to the 2000 Super Bowl aged 63. Chicago Bears icon George Halas was still coaching in the NFL at 72.

He probably didn't make ESPN's database, but let's not forget Bart Cummings saddled up So You Think as favourite in last year's Melbourne Cup a week before his 83rd birthday.

Generally AFL clubs appoint young coaches, a point even the veterans of the commentary box keep pushing for reasons that seem a little perverse, given most of them are nearer to 60 than 30.

The oldest appointee in recent times was Denis Pagan, aged 55, when he took over at Carlton in 2003, and despite his record (Team of the Century coach of the Kangaroos) is now considered past it (for reasons we've yet to understand).  Jeans was 59 years old when he took on the Tigers for one year in 1992 and John Kennedy 56 years old when appointed to North Melbourne in 1985. Ron Barassi was 57 when he came out of retirement to lead the Swans in 1993. 

The average age of AFL coaches right now is 42.47 years with three coaches in their 50s and six in their 30s, with an average coaching experience of just 120.23 games per coach. Take Mick Malthouse's average games experience (he has now coached 650 matches at three clubs) out and the average becomes 87.12 games per remaining 16 coaches.

Back to McKeon - he started out in 1973 with the Kansas City Royals, has been sacked four times, and retired once. That, at least, sounds normal.