September 19, 2021 | World Rugby’s sub rule: It is still about injuries, not size


Cheslin Kolbe of Toulouse looks on during the European Champions Cup match against Gloucester at the Stade Ernest-Wallon in Toulouse on 19 January 2020.

Cheslin Kolbe of Toulouse looks on during the European Champions Cup match against Gloucester at the Stade Ernest-Wallon in Toulouse on 19 January 2020.

  • Renowned sports scientist Tim Noakes believes World Rugby’s reported aim to reduce the number of replacements during a game would be a “retrogressive” step if implemented.
  • He also notes the debate should not focus on size, rather how it increases the risk of injury because already overplayed players have to be on the field longer.
  • But former Springbok coach Carel du Plessis, who admits he is a purist, hopes a smaller bench could in future promote more skillful players as well as the “perception of better opportunity” for smaller ones.

“South African rugby” and “size” are two phrases that are enduringly synonymous.

It is an issue that is back in the spotlight following reports World Rugby is investigating the possibility of reducing the number of substitutes allowed in a match squad.

The popular argument, held notably by people like England coach Eddie Jones, is the game needs to bring back the “element of fatigue”, that it needs the dynamic of tiring players in the latter stages of a match.

Also – as Eanna Falvey, World Rugby’s head of medical, noted – it could promote player welfare by forcing them to shed weight in order to keep the lungs going for longer.

And lighter players lead to lighter collisions.

At least that is how the theory goes.  

Yet, Professor Tim Noakes, the renowned sports scientist, believes the debate’s focus may be misguided.

“I don’t think we should be focusing on size,” he told Sport24.

“The thing that strikes me immediately is what such a move would do to longer-term player welfare. I still maintain that our players are playing too much rugby. 

“A smaller bench means that players will be required to be longer on the field. That adds to their already heavy workload and stretches their bodies even further. You’re actually increasing the risk of injury.”

Former Springbok coach Carel du Plessis, who heartily admits he is a purist, though is more of an optimist on the matter.

“I’m not scientist and I’ll be the first to acknowledge the need for proper scientific study,” the man labelled the “Prince of Wings” during a fruitful playing career told Sport24.

“It’s undeniable that the profile of the so-called prototype South African player has changed. They’ve become dramatically bigger and heavier. As a coach, you’re now required to pick a back that’s over 90kg and a forward comfortably over 100kg in general to be competitive.

“I just wonder if the premium on size still hampers us in terms of skills development. There are certainly many professional players that are big that are also outrageously gifted but there isn’t always a positive correlation.”

The rise of Springbok pocket rocket Cheslin Kolbe provides ample evidence of more diminutive players’ ability to mix successfully with the behemoths.

But Du Plessis believes the 26-year-old star is an exception.

“I don’t think you’ll immediately change the overall physical profile of the sport. However, I’m a firm believer of increased participation at lower levels.

“If a rule like the numbers of substitutes at least creates the perception of more opportunity for a smaller player, then we’re already on an interesting new path. We’re losing school players because they feel they can’t make it with their frames,” he said.

“Also, let’s not be in denial about certain positions. You need a big front row and you need a tough lock and an imposing flanker. But maybe we can also reach a stage where coaches can pick a more balanced mix in his match squad – one that combines power with skill.”

Noakes warns that ideal is unrealistic.

“This is how rugby has evolved. You need size to compete in this professional era, it’s non-negotiable,” he said.

“More substitutes mean you at least have more fresher bodies on the field to cope with the intensity. Not fewer tired ones. I’d be surprised if the law is changed as it would be retrogressive. It would go against World Rugby’s previous efforts to promote safety.” 

This post originally appeared on and written by:
Heinz Schenk