Germany midfielder Christoph Kramer was disoriented and confused after taking a heavy blow to the head early in the World Cup final, according to the match's referee.

"Shortly after the blow, Kramer came to me asking 'Ref, is this the final?'" Nicola Rizzoli told the Gazzetta dello Sport on Thursday. "I thought he was joking and made him repeat the question and then he said, 'I need to know if this is really the final.' When I said, 'Yes,' he concluded, 'Thanks, it was important to know that.'"

Rizzoli said he let Germany midfielder Bastian Schweinsteiger know about the exchange during Sunday's game but Kramer continued playing for 14 minutes following the collision with Argentina defender Ezequiel Garay.

He was eventually replaced in the 31st after slumping to the ground with a suspected concussion. Germany went on to beat Argentina 1-0 in extra time to lift the trophy.

Kramer's continuation in the game after suffering an apparent concussion revived concerns about the way football deals with the issue, as there were worrying head injuries for several other players earlier in the tournament.

Argentina players Javier Mascherano and Pablo Zabaleta also played on in their team's semifinal against the Netherlands after hard knocks to the head. And Uruguay defender Alvaro Pereira refused to leave the field after being hit in the head during the group stage.

The incidents have led to debate over whether Fifa should allow a temporary substitution so a player can get a head injury properly checked. Fifa medical chief D'Hooghe doesn't oppose the idea.

As for the rest of the match, Rizzoli defended his decision not to award a penalty to Argentina when Germany goalkeeper Manuel Neuer ventured to the edge of his area and jumped on top of forward Gonzalo Higuain to punch a dangerous ball away.

"I was wrong to give Germany a free kick. It was nothing," Rizzoli said. "Why was it a penalty? Neuer went for the ball before the attacking player."

Rizzoli also explained why he didn't show a second yellow card to Sergio Aguero late in the match when the Argentina forward challenged Schweinsteiger while leaping for a ball - leaving the midfielder with a bloodied face.

"I judged it involuntary and that's why it didn't warrant a yellow card," the Italian referee said. "I could have been wrong."

Javier Mascherano also already had a yellow card when he made a physical challenge on Schweinsteiger, but he escaped being sent off, too.

"It's important to look at players' reactions," Rizzoli said. "We were in extra time and lucidness was at the minimum. ... In a fair final like the one in Rio, the referee can't become the protagonist by rapidly sending players off."