Wolfsburg manager Felix Magath has confirmed the club have yet to receive an acceptable offer for Diego, despite admitting that the player has been in contact with Atletico Madrid.
The Brazilian is free to leave the Volkswagen Arena this summer after falling out with Magath at the end of last season.
The 26-year-old, who cost the club €15.5million from Werder Bremen last summer, was fined by the club in May when he stormed out of the team hotel upon being told he would not be starting a crucial relegation clash against Hoffenheim.
With the transfer window due to close next week both club and player now face a race against time to sort out a move, otherwise Diego risks being stuck in the reserves until at least January.
Magath openly admits the Brazilian has been talking to La Liga outfit Atletico, but neither they nor any other club have made an offer.
"Diego is in contact with Atletico, but we aren't," said the former Bayern Munich and Schalke boss.
"Therefore, there is no offer worthy of mention."