The enshrined, often arcane laws that govern cricket are known to deliver almost as many anomalies as they do certainties.
Some of those curiosities remain rooted in tradition, such as that which sees Jackson Bird robbed of the right to double the number of catches he’s held in Test cricket because the pair he claimed yesterday don’t count.
Simply because he was on the field as a substitute.
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The purists arguing that if 12th men had catches added to their career statistics then the likes of uncapped Queensland pair Chris Sabburg and Marnus Labuschagne – who earned acclaim for their key role in dismissals in successive Gabba Tests while acting as fill-ins – would need to be recognised as international cricketers.
Others are the by-product of the game’s slowly changing face.
Like the sometimes quoted scenario of a batting team requiring one run to draw level from the final delivery of a match, whereupon the player on strike is hit on the pads and completes a leg bye as the ball rolls to the third man boundary, at the same time as being adjudged out lbw by the on-field umpire.
At which point the batter immediately calls for a review, which shows the decision to be incorrect and the verdict overturned, but the decisive run(s) don’t count because the ball’s deemed to be dead and the bowling team wins.
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The sort of incident that could lead fractious rivals to the brink of war.
But in the case of ever-increasing calls to allow the use of a concussion substitute as vigilance and awareness over the effects of brain injury grows, there is an even murkier premise that prevents progress being made.
And that is the inability of the game’s governors to guarantee that any such change to the game’s playing conditions won’t be applied in a corrupt manner, enabling teams to swing players in and out of matches for no legitimate reason.
The issue of the concussion substitute, which Cricket Australia last year unsuccessfully lobbied the International Cricket Council to recognise at first-class and elite limited-overs level, became a talking point today after Matthew Renshaw was ruled out of the remainder of the third Commonwealth Bank Test against Pakistan.
The Australia opener had been struck a blow on the metal grille of his batting helmet on Tuesday but, after being assessed on the field by Bupa Support Team Doctor Peter Brukner and then subjected to extensive testing at day’s end, was deemed fit to continue his innings that ultimately ended on 184.
But when Renshaw copped a second blow yesterday, near the base of the back of his helmet as he instinctively ducked for cover at short leg, he was advised to leave the field despite appearing to suffer no immediate ill effects.
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In that intervening 15 minutes between getting hit and walking off, the 20-year-old had developed a headache, a touch of dizziness and slight nausea so he retired to the dressing room where he showed improvement in the hour before stumps.
He then underwent the full range of CA concussion protocols, recently enhanced and mandated in the wake of Phillip Hughes’s tragic death, which showed no impairment to his balance, memory or cognitive function in keeping with baseline measurements recorded for every Australia player at the start of the summer.
However, Brukner – a former Australia Olympic Team doctor and head of Sports Medicine and Sports Science at Liverpool Football Club – was concerned about Renshaw’s ongoing headaches and the fact that he continued to feel unwell this morning.
He was diagnosed with concussion, and Brukner advised national coach Darren Lehmann that the young batsman would be withdrawn from any further involvement in the remainder of this Test in line with the CA Concussion and Head Trauma Policy.
A decision that, according to Brukner, Lehmann accepted without question even though it left him a player short with Australia likely to bat soon after play resumed on day four.
But it’s safe to assume the Australian team management, and even the affected player himself, might not have remained so sanguine had the Test match scenario been vastly different and Pakistan was the side driving hard towards victory.
"The more experience we have with this, and the more common it is then the more pressure will be on the ICC to do something about a concussion sub,” Brukner said today as the resumption of play on day four was delayed due to rain.
"The concern we have is there is a tendency for the player, and coaches and so on, to want to continue (to take part in matches after suffering a head knock) because they don’t want to let the team down.
"They don’t want to be a player short.
"In this case, I have to say the coach and the captain have been absolutely supportive and have said to me all along ‘it’s your decision Doc’.
"I’ve had no pressure to keep Matthew in the game, when I told Darren (Lehmann) this morning that Matthew was out (of the final two days of the match) he said ‘fine, that’s your decision Doc, we’ll work around that’.
"But the concern we have is that without a concussion sub there is a lot of pressure on the player and the coach and the doctor to allow the player to continue.
"So it would be helpful in that regard, it would make it easier to pull players out with a concussion.
"But that’s for the ICC and the politicians to sort out.
"I’m just more concerned about looking after Matthew."
Cricket Australia last year became the first governing body among Test nations to legalise the use of concussion substitutes in non first-class matches conducted under its auspices.
A decision that flowed from recommendations contained in the Curtain Report, an independent investigation examining practices and safety protocols in the wake of Hughes’s death in November, 2014.
But a push from CA to have the measure adopted for all international fixtures by the ICC’s influential cricket committee, and which would then have required ratification by the full ICC board, was unsuccessful.
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With the game’s ruling body decreeing in June last year “that the current laws and playing conditions allow players to receive the best possible medical treatment, and further change to the regulations in this area is not required at present”.
Given that any push by CA to have the change introduced to Sheffield Shield matches and other three or four-day fixtures in Australia (such as tour matches) would rob them of their first-class status, the concussion substitution policy remains restricted to list-A, limited-overs and other domestic matches over which CA holds authority for playing conditions.
It is understood that key among the reluctance of the ICC Cricket Committee, which includes Lehmann among its members, to allow teams to bring in a replacement player as substitute for anyone ruled out of a match due to concussion (as with Renshaw) is the potential for the practice to be misused.
The same rationale that underpinned the ICC’s 2011 decision to ban the use of runners for injured batters, a practice that some international claims was being manipulated by teams to gain an advantage.
The fact that concussion, unlike bone fractures or muscle tears, can’t be definitively diagnosed other than through symptomatic testing means there remains a chance a player might be replaced during a match even though they are not legitimately suffering a debilitating head injury.
However, staunch advocates for the practice such as Brukner believe the risk of allowing a concussed player to continue in a game – and possibly risk further, serious injury – outweighs the potential risk to the integrity of the sport.
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And eliminate the peril that ex-Australia Test opener Justin Langer was prepared to put himself during a famous match against South Africa at Wanderers in Johannesburg in 2006.
When Langer, playing his 100th Test, was poleaxed by a bouncer from Makhaya Ntini first ball he faced, and spent several days in a darkened hotel room before returning to the ground as Australia lurched between victory and defeat on the final day.
Contrary to medical advice and the orders of his captain Ricky Ponting, Langer donned his playing kit and vowed he would face the bowling if it reached the point where a few runs were required for Australia to win and he was the last remaining batter.
For his part, Ponting threatened to tackle Langer to the ground if he attempted any such foolishness given the very real risk that he might suffer serious injury if he was struck again.
As it transpired, neither scenario was visited when tailenders Brett Lee and Michael Kasprowicz carried Australia across the line.
But it’s a situation that would not arise if a player demonstrably affected by concussion – as Langer was after that sickening blow – could be replaced and the team not disadvantaged.
"We’ve introduced it into the non first-class cricket in Australia and it seemed to be successful," Brukner said of the initiative that was enacted for the first time during last October’s Matador BBQs One-Day Cup tournament.
"I think it’s something that needs to be looked at very seriously by the ICC."