Ajax reached the semi-final of the Champions League last season, beaten narrowly by Spurs before they lost star duo Frenkie de Jong and Matthijs de Ligt.
This summer they will lose Ziyech for £36.6million, while Arsenal are among those to have expressed interest in securing a deal for 29-year-old Blind.
Mikel Arteta is planning a summer overhaul at London Colney with Football.London reporting last week that as many as six players could be axed to fund new additions.
Arteta has already brought in defenders Cedric Soares and Pablo Mari from Flamengo, but he seems intent on remodelling his whole rearguard and Blind apparently fits the bill.
The former United midfielder, who left for £14million in July 2018, has since switched to being a reliable, ball-playing centre-back, just what Arteta is believed to be looking for.
Blind has featured 28 times for Ajax this season and is under contract until 2022, but he is also understood to have numerous other suitors.
Blind joined United in 2014 and made 90 appearances and scored four goals.
During his time at United Blind won the FA Cup, Carabao Cup, Community Shield and Europa League.
On 21 December 2019, it was revealed Blind had been diagnosed with Myocarditis, and had been fitted with an Implantable cardioverter-defibrillator .