Is Mark Boucher the new Jack Blackham?

As we know, Mark Boucher recently broke the world record for wicket-keeping dismissals and became the first keeper to take 400 dismissals. This invariably starts people wondering about the question of who the best wicket-keeper ever is.

I don’t plan on answering that question here, but I am going to make a suggestion as to how we can create measurements that allows us to more accurately compare keepers over time.

We do not have any reliable data on dropped catches and missed stumpings, so we cannot create a ‘fielding percentage’ similar to baseball. There are two measurements that we do have of wicket-keepers: dismissals and byes conceded. For the purposes of measurement, I am going to look at dismissals as a percentage of team dismissals and byes conceded per 100 balls kept. And, although wicket-keeping purists may not like it, we can also consider batting ability. So, with apologies to the Keith Andrews and Richie Ryalls of the world, I am going to include batting average.

Now, the role of the keeper, and with it the measurements have changed over time. A lot of this is to do with the fact that keepers used to stand up to the stumps a lot more in the past than they do today. In modern cricket keepers have a higher percentage of dismissals, lower rates of conceding byes, and are expected to score more runs than in the past. The table below shows how these numbers have changed over time:

Period	Bat Avg	%Dis	%Byes
1877-1914	16.43	11.76	1.28
1919-1939	23.56	14.23	0.93
1946-1970	22.45	17.39	0.70
1971-1990	25.10	19.38	0.63
1990-2007	29.75	20.43	0.62

So, let us consider Mark Boucher and Jack Blackham. Blackham played in the first ever Test in 1877 and represented Australia in 35 Tests between then and 1894. Boucher has a dismissal percentage of 23.09, byes conceded rate of 0.65 and a batting average of 30.21. Blackham’s figures are 11.36, 1.38 and 15.63, respectively. Boucher’s figures are basically twice as good as Blackham in all departments.

My suggestion is that we create an era adjusted measure by dividing the keepers stat by the overall average of all other keepers who played in the years that they played and multiplying it by the current average (i.e.20.43 for dismissals, 0.62 for byes and 29.75 for batting from the table above).

This produces a very interesting result if we compare Boucher to Blackham. Boucher’s adjusted figures are 23.80 for dismissals, 0.61 for byes and 29.40 for batting. No great change as there, as he is currently playing. Blackham has 23.59 for dismissals, 0.79 for byes and 29.46. Which are remarkably similar, especially in dismissals and byes.

So, here are the tables for the leading 5 keepers in each of the adjusted measures (with a minimum of 20 Tests as wicket-keeper):

Percentage dismissals

Name	Adjusted	Actual
GRA Langley (Aus)	29.02	21.92
AFA Lilley (Eng)	28.53	15.54
CO Browne (WI)	28.13	27.36
H Strudwick (Eng)	27.01	16.47
ATW Grout (Aus)	25.01	21.61

Byes conceded per 100 balls

Name	Adjusted	Actual
H Carter (Aus)	0.27	0.74
PR Downton (Eng)	0.27	0.28
DJ Richardson (SA)	0.34	0.33
WAS Oldfield (Aus)	0.36	0.64
Khaled Mashud (Ban)	0.36	0.40

Batting average

Name	Adjusted	Actual
LEG Ames (Eng)	63.46	43.40
A Flower (Zim)	56.80	53.70
AC Gilchrist (Aus)	49.44	48.66
Imtiaz Ahmed (Pak)	44.56	30.45
H Carter (Aus)	44.37	22.97

Note that only matches where the player was the designated keeper are included. If they played as a specialist batsman this is excluded. We do not have full details for when keepers were replaced during a match, so it is assumed that the keeper kept for the whole game. This could affect the byes calculation marginally.

Note also that this does not suggest that Les Ames, for example, would average 63.46 if he were playing today. It is simply a measure compared to contemporaries, i.e. if Ames were playing today and was as far ahead of current keepers in terms of batting average as he was in his day then he would average 63.46.

Of course, we still do not have a measure for that other great skill required from modern wicket-keepers: Encouraging the bowlers. You know, the incessant “Great bowling … “ comments after each ball. Sometimes emitted mere nanoseconds before the half-volley is eased to the mid-wicket boundary. But, the TV technology whizzes may be working on this as we speak. Soon ‘Keeper-o-Meter’ will give us measurements of decibel levels, volume and quality of encouragements. And then statisticians will be able to correlate this to wickets falling.