Sunderland have agreed a deal to sign former Millwall attacker Aiden O’Brien, Football Insider can exclusively reveal.

The 26-year-old is a free agent this summer after his contract with the Lions expired earlier this month.

A source at the Stadium of Light told Football Insider that the forward has agreed a deal to sign for the Black Cats.

Phil Parkinson wants to build a squad capable of mounting a serious bid for automatic promotion next season and sees O’Brien fitting into those plans.

The winger scored four goals in 21 appearances for the Championship side last season but struggled for regular game time at The Den.

He has been capped five times by the Republic of Ireland and was given his international debut by former Sunderland boss Martin O’Neill.

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Parkinson has already lost a sizeable chunk of his squad this summer with Jon McLaughlin, Kyle Lafferty and Jack Baldwin all completing moves away from the Stadium of Light.

While first team players Alim Ozturk, Duncan Watmore and Joel Lynch have been released.

The future of Aiden McGeady remains in doubt after Charlton, where McGeady spent the second half of the 2019/20 campaign on loan, were relegated on the final day of the Championship season.

O’Brien came through the academy at Millwall and has gone on to score 44 goals in 226 appearances for the Lions, following his debut in 2011.

He can play on either flank as well as a striker and would provide a significant goal threat for the League One giants next season.

In other Sunderland news, Kevin Phillips has told Football Insider that he has been called by the lead of a consortium that is interested in buying the club.

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