Despite making 36 appearances for United in all competitions this season, De Gea is now regarded as second choice behind Dean Henderson.
The Spain international did not take his opportunity to impress in Wednesday's Europa League final, failing to save 11 spot kicks in succession as United lost to Villarreal in a penalty shootout.
According to The Sun, United intend to make a fresh attempt to sign Oblak during the summer transfer window as they bid to solve their issues between the sticks.
Acknowledging that Atletico would demand big money for a stopper deemed by some to be the best in the world, the Premier League outfit are happy for De Gea to return to his former team in part-exchange.
De Gea still has two years remaining on his contract at Old Trafford. body check tags ::