Aaron Cruden a better kicker than Dan Carter?

Graham Henry commented last week on Aaron Cruden’s place kicking as one of the reasons he was selected in the All Black squad.

Media comments in New Zealand have recently pointed out that Cruden had a higher Super Rugby kicking percentage than Dan Carter.

To an extent, they are right.

At the end of the Super Rugby round-robin Cruden’s placing kicking success rate was 80 per cent or 36 from 45 attempts, and Carter was 72 per cent or 50 from 69 attempts.

As astute Roar readers have commented, the success rate doesn’t take into account difficulty. This is true and so I compared the difficulty of each of Cruden and Carter’s kicks to see if there was a difference.

I can undertake this as I have a database of place kicks from the last ten years from a variety of competitions and professional rugby union kickers. From this, due to the volume of kicks taken, a probability of success can be calculated of another kick taken in the same circumstances. For example, if 73 per cent of all the kicks in similar circumstances are successful, then you would expect the kick to go over 73 per cent of the time, in the same circumstances.

My database provides a map of the field so the element of difficulty such as distance, angle, conditions can be applied. The database differentiates between conversion and penalty attempts as there are differences in the probability of success.

When I looked at the probability of success (POS) for each one of the kicks for Cruden and Carter (Super Rugby round-robin) it was clear that 33 per cent of Cruden’s attempts were in front of the posts. As you would expect the POS for these kicks is 95-100 per cent. Carter only had 12 per cent of his attempts in this 95-100 per cent POS range. Unsurprisingly, both kickers made those kicks.

Determining their first miss working back from the goal posts, which decreases the POS, coincidently they both missed one of their attempts in the 80-84 per cent POS range.

What is interesting is that just over half (56 per cent) of Cruden’s attempts are in the 80-100 per cent POS range, compared to Carter’s attempts where only a third (33 per cent) are in the 80-100 per cent POS range. You have to go back from the posts to 65-100 per cent POS range for Carter to have the majority (54 per cent) of his kicks. So clearly applying difficulty, a real difference between the kickers has emerged.

Looking at kicks that have a 50/50 or lower POS, Cruden has taken fewer attempts in this area, 18 per cent, compared to Carter having 38 per cent of his attempts in the 50/50 range. Carter also attempts more difficult kicks. He has had two penalty attempts that had a 25 per cent POS range, getting one of them.

Whereas Cruden’s most difficult kick was a conversion miss where the POS was 35-39 per cent.

To be fair to Cruden, eight of his attempts were in the 50/50 POS range where he’s got half of them. Carter also got half of his 26 attempts in that 50/50 range. So both players are similar in converting attempts into points from this range.

Henry also said Cruden had been place kicking better in the last couple of weeks but from my analysis he has had the same type of kick difficulty in the last couple of week as all season, so I can’t agree.

However, I don’t keep data on whether his kicks for touch or back in the field of play are longer as Henry stated.

Clearly if over half your kicks are in relatively easy spots to take, you will have a higher kicking success rate than someone taking more difficult kicks. That is what Cruden has had this Super Rugby season. Taking difficulty into account, Carter has had the more difficult kicks and will also attempt harder kicks, based on this year’s Super Rugby.

It will be interesting to see what happens in the Tri-Nations and Rugby World Cup games, where Cruden might not have a captain asking him to kick easy penalties or team mates running the tries under the posts.