Joachim Low has told Manuel Neuer he must gain match practice if the Germany captain is to be part of his country's World Cup defence.
Bayern Munich goalkeeper Neuer was named in Low's provisional 27-man party for Russia 2018 on Tuesday despite not playing since September following foot surgery, although he has now returned to full training.
The 32-year-old could make a high-profile return in Bayern's DFB-Pokal showdown with Eintracht Frankfurt on Saturday, while Germany have scheduled pre-tournament friendlies against Austria and Saudi Arabia.
"Neuer is back in full training and we want to see and judge him in the training camp," said Low, who has named Barcelona's Marc-Andre ter Stegen, Bayer Leverkusen's Bernd Leno and Kevin Trapp of Paris Saint-Germain as his other goalkeepers.
"Both sides are aware of their responsibilities. We will be open and honest after the training camp, and without match practice, you can't go into a tournament.
"But right now, things look good. He's our captain and we hope that he can go into the tournament 100 percent fit."
Neuer's Bayern team-mate Sandro Wagner has missed out – the striker's decision to leave Hoffenheim in January to play second fiddle to Robert Lewandowski at the Allianz Arena ultimately backfiring as Low selected uncapped Frieburg forward Nils Petersen.
"We had to make a decision, and it was made in favour of [Mario] Gomez and Petersen," Low said.
"I know that those players [who missed out] are just very disappointed because they worked hard for it. Sandro has shown his class when with the team."
An enviable array of attacking options is enhanced by Borussia Dortmund's Marco Reus, whose extensive catalogue of fitness problems served to rule him out of both Euro 2016 and the previous World Cup.
"I am happy that he has played the last few months without injury," Low added.
"Marco is a special weapon and has a lot of strong attributes – speed, instinct, feeling for the spaces, game intelligence. He promises a lot."