A year before they host the World Cup, Russian football has come under the spotlight amidst fresh allegations of drug abuse.
Canadian lawyer Richard McLaren, the author of an explosive report into Russian doping, has told German broadcaster ARD he has new evidence suggesting that positive tests taken from Russian players were swopped with clean samples.
Loew says any footballer caught doping must be named and shamed.
"It's an ongoing investigation and I don't want to heat the speculation," said Loew in Wednesday's press conference ahead of Germany's Confederations Cup semi-final against Mexico in Sochi.
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"The anti-doping agencies and FIFA (world football's governing body) should call a spade a spade, then we will see what happens.
"Should it (the allegation) be true, I want to hear names from the institutions who regularly test us.
"If players have doped, they should be suspended and banned."
McLaren said the World Anti-Doping Agency had seized 155 samples from 2018 World Cup hosts Russia for re-testing, with FIFA kept informed.
A report from the UK media over the weekend claimed FIFA is investigating if Russia's 2014 World Cup squad were part of a state-run doping scheme, but no players from the finals three years ago in Brazil returned a positive test.