That's one question that ran through the minds of many fans watching the World Cup final between Germany and Argentina, astounded by the surprise last-minute inclusion of the little-known Bayer Leverkusen defensive midfielder.
By the end of the 31st minute, the 23-year old - who played for Borussia Monchengladbach last season on loan in the Bundesliga - had become world famous for far more concerning reasons than a player making his competitive Germany debut on football's biggest stage.
Struck in the head following a nasty collision with Argentine defender Ezequiel Garay in the 19th minute that forced him to the ground, Kramer was cleared to play on. Thirteen minutes later, his World Cup dream was over as he was helped off the pitch by ground staff, clearly looking confused and shaky on his feet.
That was the extent of the blow he had suffered earlier and it wasn’t the first time such an incident had happened in the World Cup.
In a crucial group-stage match against England, Uruguay defender Alvaro Pereira lay motionless on the ground for seconds after a collision with winger Raheem Sterling. Judging by the negative body language of the team doctors who examined him, it seemed like his match was over but, with coach Oscar Tabarez ready to substitute him, the Inter player furiously insisted on carrying on. Heavy criticism later followed.
Similarly, in the second semi-final, Argentina enforcer Javier Mascherano went down while challenging for a header with Netherlands midfielder Georginio Wijnaldum and, like Pereira, appeared to have lost consciousness for a while before being stretchered off. Much to the relief of the fans and head coach Alejandro Sabella, however, the Barcelona player was back on the pitch, albeit with a dazed look on his face.
On the same night, full-back Pablo Zabaleta was also struck in the face, but following some medical treatment was fit to continue. But unlike the other incidents, Argentina had used up all their substitutions, meaning the Manchester City defender had no option but to somehow make it through the last few minutes of an excruciating tie.
Even if Sabella had substitutions left, would Zabaleta have allowed himself to be replaced? Of course not. We have seen that numerous times over the course of the tournament, with Pereira and Mascherano perfect examples, while Kramer tried his best until he simply could not continue on.
After all, it's the World Cup, and no player would want his team to suffer by using up a crucial substitution, unless absolutely necessary. These are professionals who take immense pride in their national shirt, so much so that they would be willing to ignore the drastic consequences of a severe blow to the head.
It therefore begs the question whether it's high time Fifa considered changing the upper limit on the number of substitutions allowed per team in competitive games.
Is it time teams are allowed some sort of a 'reserve substitute' who may be allowed to come on in case of serious injuries, specifically head injuries that require immediate examination?
The current rules in a way force the players to continue despite the risks involved with head injuries. On average, it takes a doctor close to 10-15 minutes to properly examine such cases to make sure there is no evidence of concussion.
Rugby union understood the risks, trying out new rules two years ago which allowed players to come off the field for proper examination while a replacement temporarily took to the field. Recommendations to remove the player could be made by the referee after consultation with the independent match day doctor or the team doctor. Earlier in such scenarios, players with symptoms of concussion were assessed on the field and would either be allowed to continue or taken off without replacement.
Perhaps it's high time football draws inspiration from its cousin to implement laws that help protect the players. Such a change will not only put less pressure on the players themselves, but also the coaches and - more importantly - the doctors, who today have to run quick-fire tests while their team battles it out on the field with a man down. Every minute wasted off the field is an extra minute in which sides can suffer with a man less.
Of course there is a possibility such rules could be misused - rugby was rocked by the 'Bloodgate' scandal which saw Harlequins' Tom Williams fake a serious injury to force through a substitution - but which rule isn't? Players often dive and playact to prompt cards for their opponents but does that mean rules regarding cautions are not important? The fundamental concern is the well-being of the footballer himself, who today falls prey to the stringent substitution laws of the game.
The World Cup incidents were just the tip of the iceberg as such serious head collisions happen quite often over the course of a season in club football. The one involving Tottenham goalkeeper Hugo Lloris and Everton's Romelu Lukaku last November is still fresh in the mind. Then-Spurs boss Andre Villas-Boas even went on to admit later that the Frenchman insisted upon staying on, despite not remembering the accident.
"The lights went out" is how Pereira described the blow to his head, while new world champion Kramer has admitted he remembers very little of his Maracana debut.
Isn't that worrying enough already, or are we actually waiting for the lights to go out completely before we finally spark a change?
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