Khedira was forced off in Germany's recent friendly draw with Italy having suffered significant ligament damage in his right knee following a tussle with Andrea Pirlo.
The midfielder is set to miss the majority of the season due to the problem and could struggle to be ready for the tournament in Brazil next summer - and Netzer believes the Nationalelf would feel his absence keenly.
"It is irresponsible to speculate on whether Khedira will play in the World Cup as the healing process after torn ligaments is different depending on individuals," Netzer wrote in Bild. "His absence would be bitter in any case because Khedira plays not only a sporting role in Löw’s plans but also as an anchor and leader of the team."
Despite the blow of losing Khedira, Netzer believes Low has a huge depth of midfield talent to choose from should the need for replacements arise.
"He has a much larger selection of quality players than in recent years," Netzer continued. "With the Bender twins, Lars and Sven, he has two midfielders that are most suitable for defensive tasks. This also applies to Phillip Lahm who at Bayern has recently been played in a defensive midfield position."
Netzer also gave his support to Borussia Dortmund goalkeeper Roman Weidenfeller to make the squad following his international debut against England last week at the age of 33.
"Weidenfeller is an older, strong and experienced goalkeeper, whose good character can pay off for the team. Therefore the nomination of Weidenfeller would be justified," added the Borussia Monchengladbach legend.