Best bowlers of the last 50 years

During a rain delay at Johannesburg last week, the radio commentators were putting an all-time England XI together. The usual arguments ensued: how can you compare players across eras? Is bowling average the sole measure? While looking at something quite unrelated, I realised I’d stumbled upon a new way of comparing players which is perfect for this question.

The metric is “percentage impact on batsman’s average”. For instance, batsmen generally scored 31% below their average facing Malcolm Marshall, making him the best Test bowler of the last 50 years.

Here’s the bowlers since 1970 with at least 150 wickets at under 25 apiece, ranked by their impact on a batsman’s average:

Fig 1 – Impact on Batsman’s average, leading bowlers of the last 50 years in Tests. Note that these have been adjusted to reflect players like Ravi Jadeja who has mostly played at home, mainly when conditions favour a second spinner.

There are four other players whose average flatters them, where Impact on Batsman’s Average is a better metric. Joel Garner picked up 92 of his 259 wickets against a mixed England team. Muttiah Muralitharan and Waqar Younis benefited from a disproportionate number of games against Bangladesh, Zimbabwe and (in Younis’ case) Sri Lanka. Wasim Akram is the hardest to explain: 38% of his wickets were against batsmen with career averages under 20 (a 25% figure would be more normal).

Did you spot Vernon Philander muscle in at fourth on the list? A phenomenal bowler. His average (and Impact on Batsman’s average) may be boosted by favourable conditions where he happened to play most of his away games: England, Australia and New Zealand. Still, I won’t fudge the numbers: he has a brilliant record and South Africa will miss him.

Here’s a comparison of Philander and Muralitharan

Fig 2 – Philander was better than Muralitharan.

Contextual Averages

England have been defending Joe Denly’s average (30) lately by saying that his performances are better than they appear because of the conditions he has played in.

This piece supports that approach: Marshall and Garner had the same bowling average, but Marshall was 10% better than Garner. If averages can mask that kind of difference over a whole career, imagine how skewed an average could be after ten Tests.

Further Reading

ICC’s all time rankings. The ICC have listed players according to their peak performances, while I have used their career. Consider Akram – his average puts him fourteenth on the list, but accounting for who he dismissed the ICC rankings take him all the way down to 76th. That supports my calculations that he had a -11% impact on batsmen’s averages.