Debut – Red Ball Data

On the use of unfamiliar bowlers

England just whitewashed Pakistan away from home. Two innings of spin played a major part.

First Test: debutant Will Jacks took six wickets, outperforming xW by 2.5*. Third Test: debutant Rehan Ahmed took five second innings wickets for 48, outperforming xW by 3.5 (ie. on average it was really a 1-point-five for).

Jacks’ performance was on a surface where at one point 882 runs had been scored for the loss of ten wickets. Jacks has only bowled 411 first class overs, and 46 of them were at Rawalpindi.

I have a theory: unfamiliar spinners get a boost, relative to bowlers whose variations have been publicly scrutinised in HD. The boost is measurable by the outperformance vs xW (ie getting more wickets than you’d expect given the quality of balls bowled). We can’t test this directly (I don’t have the data, plus it’s subjective to know who is “unfamiliar”). But we can test a proxy: performances on debut.

The first two columns of the below chart show how it used to be. Lots of promising bowlers get a chance, very few succeed. Most wickets are take by the best bowlers (Murali & Warne) at a low average. These days that trend has reversed.

What’s driving that? I’d suggest it’s the element of mystery – spinners come in many forms, and each has a subtly different style and (possibly) variations. In the 1990s a top bowler may have been able to surprise batsmen with old tricks. Little chance of that these days. Already we know Rehan Ahmed bowls with a high arm, his leg break doesn’t turn as much as the googly, both deliveries have a scrabled seam with lots of topspin. And that’s just from one game.

There are probably some secondary factors, such as better selection, more judicious use of a second spinner, and fewer stars around to bring down the average of non-debutants.

If unfamiliar spinners have an advantage, there is an incentive to give the old ball to any vaguely capable new Test batsman. Keep an eye out for it in future, especially with England.

Take from this that one swallow does not a summer make. Give a spinner a few games to see what he’s made of**. Then we’ll decide if you’ve found the next Swann.

*I think. Didn’t write it down and Cricviz take stats off the app sharpish these days.

** Note the deliberate use of “he” – these stats aren’t based on the women’s game; so it would be inaccurate for me to assume the same principles apply.

Appendices

Leg spinners get better as their careers go on (courtesy of @sanderson_club). Rule of thumb: takes 700 overs to reach their peak.

2. Rehan Ahmed xW – scraped from CricViz’s app.

3. ODI Spin Debutants – Note how wide the gap used to be between debutants and all spinners in ODIs. Just like in Tests.

4. The same trend does not apply for pace bowlers

Top five Test batsman to debut in the last eighteen months

I was on the latest Cricket only Bettor podcast talking about promising Test cricketers. Here are my thoughts in more detail.

It can be difficult to judge Test players after a few innings. Their Test average is likely to be meaningless. First Class records feature innings played a decade ago. The concept of “First Class” is lovely, but not all FC bowling attacks are created equal. South Africa has two levels of FC cricket, England has a couple of rounds of games against students each year.

I’ve used player records over the last four years in the top First Class tournament of their country to pick out the best batsmen that are just embarking on their Test career. Note that expected averages below are from here onwards (rather than career averages which should be adjusted up/down based on performances to date).

5. Oshada Fernando. Expected Test average 37

FC avg just 37 over his career, but this rises to 50 over the last four years. Likely to be under-rated.
39 sixes in nine FC matches last season (Jos Buttler gets a six roughly every other FC innings). Also averaged 74 last year.

Test average of 46 comes from four away Tests (in SA and Pakistan).
Hit 75* as Sri Lanka beat South Africa 2-0 in South Africa. (Before that only England and Australia had won a series in South Africa).

In December Pakistan soundly beat Sri Lanka in Karachi. Sri Lanka subsided for 212, with only two batsmen passing 20. One of those two was Fernando – he made 102.

4. Rassie van der Dussen. Expected Test average 40.

Took the long route to Test cricket: T20I then ODI experience before being unleashed in whites aged 30.

Tasted success in the 2019 World Cup with three fifties in six innings, even as SA’s campaign faltered (finishing seventh in the group).

Reasons to believe: last four years scored 2,302 runs at an average of 55. Some positive murmurs in the media from his first three Test innings.

3. Zubayr Hamza. Expected Test average 42.

1,563 runs at 50 L4yr. Career FC avg 49.97. Just 24 yrs old, quite a prospect.

Makes the list purely on First Class performances. Top order batsman, Poor start to Test career, but has a higher first class average than van der Dussen. Averaging 21 after eight innings, but I’m keeping the faith

2. Marnus Labuschagne. Expected Test average 45

He’s just racked up the most runs scored by an Australian in a five-match summer. So why isn’t Labuschagne #1? His FC record lately isn’t that good – four year Sheffield Shield average of 35.

His evolution is interesting. Averaged 25 in the Sheffied Shield in 2018/19, and only 26 over his first five Tests to 31st March 2019.

Began 2019 as an unknown (to me) player in an unfancied Glamorgan team but scored 1,114 at 66 and followed that up with a great run for Australia.

Will he keep it up? He’s surely not come from nowhere to be the best since Bradman. Has he? It depends on how you judge a player. One year? Two years? Four years? Their whole career?

1. Ollie Pope. Expected average 48.

Didn’t get past 30 in his first five Test innings, has back to back fifties since then.
Missed most of 2019 with a shoulder injury, though that doesn’t seem to have affected his game.
Hit an unbeaten double hundred in August against a Hampshire attack with four international bowlers (Edwards, Abbott, Holland, Dawson).
Has only played 34 first class matches – so there’s some uncertainty on exactly how good he is.

***

The list started as best batsmen to debut in 2019, but I could only find three batsmen that excited me enough. Thus Pope and Labuschagne got parachuted in and the list was extended to the last 18 months. Honourable mentions go to Mayank Agarwal and Rishabh Pant who would probably have made the cut if I’d been looking at the last 18 months from the start.

Debutants in Away Tests have shorter careers

Would you expect players to be disadvantaged by making their debut overseas? Surely the best players get picked and have a decent run in the side until there’s sufficient data to disprove the analysis that got them selected in the first place?

Afraid not. Away Debutants are discriminated against! Debut at home you can expect a nine Test career. If your first game is an away match, that drops to six.

Fig 1 – Average (Mean) and Median Tests played by location of Debut. Includes top nine Test teams, since 2005.

A reminder – home advantage in Test Cricket is big. Somewhere around 17%, depending on how you cut the data. If your expected batting average is 35, that’s 38 at home and 32 away. A player who starts their career overseas is likely to underperform, and is at greater risk of being dropped when the naïve assertion is made “OK, they have a decent First Class Average, but they are only averaging 29 in Tests.”

Half of Away Debutants don’t make it to seven Tests. And yet the mean number of Tests played by Home Debutants is only 1.1 matches more than Away Debutants. For some reason the early benefit to Home Debutants doesn’t persist. What happens after seven Tests to explain that?

Fig 2 – Frequencies of Number of Tests played. Includes top nine Test teams, since 2005.

The behaviour flips – from Tests 7-20 more Home Debutants are discarded than Away Debutants. I expect that this is because some players who had an easy home series to get into Test Cricket then get caught out when away from home.

After 20 Tests, a player has generally played a similar numbers of home and away Tests, so there’s no great difference between the two curves.

So What?

Some Away Debutants play fewer Tests than they deserve. Conversely, some Home Debutants are kept in the team longer than they should be as a result of the stats boost they get from playing more home Tests than away.
It’s time to move on from raw averages. Adjusted averages are the future. Not just adjusted for home/away, but also the ground they are playing on (think Headingley vs The Oval), the quality of opposition and the innings number. This is not a complicated task, and I’d be very surprised if it isn’t already happening behind closed doors. Admittedly I haven’t yet done this when rating Test players. But then, this is a hobby for me. Also, until a player has played 20 matches, I use their First Class average to appraise them. Which is coincidentally the point at which Debut Location ceases to matter as an input.
Don’t make your Test Debut in an away game if you can help it. I appreciate this is not practical advice, so instead, if anyone reading this has made their Debut in an away game, make sure you quote your home/away adjusted average whenever possible! Ebadot Hossain, am looking at you.

It’s almost the same story for ODIs

A quick calculation says Home Advantage in ODIs is c.11%, so we would expect ODI debutants to have similar trends to Tests. Which is true for matches 0-20: Away Debutants are more readily discarded after a handful of games, then Home Debutants are in the firing line from 4-20 matches.

Fig 3 – Frequencies of Number of ODIs played. Includes top nine ODI teams, since 2005.

After 20 matches it gets more interesting. Overall, Away Debutants have greater longevity on both a mean and median basis. Of the Post-2005 players with more than 100 ODI Caps, 16 began at Home, 22 began Away.

Fig 4 – Average (Mean) and Median ODIs played by location of Debut. Includes top nine teams, since 2005.

What the dickens? I can’t confidently explain this. Could have hidden it from you, but it’s interesting and therefore worth sharing, even if I don’t understand it. I’ll offer one possibility: ODI series are often tacked onto Test series, so in an away series the star Test players stay on for the ODIs, meaning that only highly regarded red ball players make the team. At home, the top Test players can more easily be rested, so lesser known players might get a go.

The Short List: Away Test Debutants

Below is the list of players that played fewer than seven Tests, and started away from home. Have a read, see if you can pick out some players who might have had 20 Tests if given the benefit of a home debut. Luke Ronchi and Owais Shah jump out at me.