The Cameroonian moved to Inter on a free transfer in the summer of 2022 and impressed for the Italian giants during the 2022-23 campaign, featuring on 41 occasions, keeping 19 clean sheets in the process.
The 27-year-old then made the switch to Man United in July, with the 20-time English champions said to have paid an initial £47m for his services.
Onana has had a difficult start to his time at Old Trafford, though, conceding 19 goals in 11 appearances, keeping only three clean sheets in the process.
The goalkeeper has made a series of high-profile errors, which has led to a host of criticism, with ex-Red Devils players Peter Schmeichel and Roy Keane among those to express concerns.
Keane recently said that the Cameroonian has «a long way to come back» after his early-season form, and his performance will again be under the microscope when Man United head to Sheffield United next weekend.
Onana penned a five-year deal with Man United, with the option of a further 12 months, and Red Devils head coach Erik ten Hag has insisted on multiple occasions this term that the goalkeeper has his full support.
However, Ten Hag could face a difficult decision if the stopper's poor form continues, with Altay Bayindir, who arrived from Fenerbahce over the summer, waiting in the wings.
Marotta was asked about a potential return to San Siro for Onana during a wide-ranging interview and refused to rule out the former Ajax goalkeeper making the switch back to Milan.
«Anything can happen in football, even if those who return do not always have positive results. It was an important
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