Germany must give Manuel Neuer every chance of featuring at the World Cup, former national-team goalkeeper Jens Lehmann has urged.
Neuer's 2017-18 campaign has been ruined by injury after the Bayern Munich keeper broke his foot in September.
The 32-year-old, who was a key part of Germany's triumphant squad in Brazil four years ago, has not played since then but did recently return to training.
Lehmann, who was capped 61 times for his country, is keen to see Neuer make the trip to Russia, but concedes he must prove his fitness by returning for Bayern's DFB-Pokal final with Eintracht Frankfurt next weekend.
"You should wait as long as you can for him," the former Arsenal star told Bild.
"If he can make the cup final against Frankfurt and the two Test internationals, it should be enough.
"But he must play against Austria and Saudi Arabia, otherwise he cannot play in my opinion at the World Cup."
Lehmann is also opposed to the idea of Neuer sitting out the group stage – where Joachim Low's men face Mexico, Sweden and South Korea – and returning for their likely spot in the knockout phase.
"If he only starts with the World Cup knockout round ... then we'll only get him at 50 per cent, and that's not enough," added Lehmann, who declared his faith in Marc-Andre ter Stegen as a replacement.