The 23-year-old is now entering the final year of his contract and the club face the prospect of losing him for nothing in 2027.
The Northern Echo reports that Manchester United are confident of winning any transfer race for Hackney given Carrick's direct working relationship with the player — the United manager managed Hackney for nearly three years at Middlesbrough before leaving the Riverside Stadium. Hackney's development under Carrick during that period is the foundation of the club's belief they can make a compelling case ahead of any rival.
Middlesbrough failed to win promotion after losing the Championship play-off final 1-0 to Hull City at Wembley last month, missing out on an estimated £200 million in Premier League revenue. That outcome makes a sale this summer almost unavoidable — Boro cannot afford to hold firm if United or another top-six side submits a bid in the region of £30 million.
Tottenham Hotspur and Crystal Palace are both expected to submit offers, according to the Northern Echo, while Leeds United, Nottingham Forest and Everton have also been credited with interest. None can offer Champions League football, which United can — a factor Carrick's camp view as significant when making their case directly to the player.
Hackney was the standout midfielder in the Championship this season, driving Boro's play-off campaign with his range of passing, intensity in the press and goal contributions. He spent much of Carrick's United tenure involved in the Championship, but the coach has spoken publicly about his admiration on multiple occasions.
United intend to sign at least two central midfielders this summer alongside the incoming Ederson from Atalanta. Hackney, at £30 million and one year from becoming a free agent, would represent the most cost-effective of those additions.