It was understood that the 25-year-old held talks with the Posh earlier this summer, but a deal was unlikely unless the Championship failed in their pursuit of top target Josh Knight.
And with Knight having signed for the London Road side on Friday afternoon, MacAnthony has confirmed it’s a ‘firm no’ when it comes to O’Nien.
Replying to a question about the Sunderland fan favourite, MacAnthony said: “Absolutely no pal….Firm No.”
The stunning £975m market values of Championship squads this season and where Sunderland rank alongside Sheffield United, Middlesbrough and co
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The versatile O’Nien is current a free agent after his deal with Sunderland expired on June 30, but the Black Cats remain hopeful that a deal can be struck.
O’Nien has been linked with a number of Championship clubs this summer with Hull City and Luton Town also rumoured to be keen on the 25-year-old – but an offer from Sunderland remains on the table.