Hackney, 23, was named Championship Player of the Year this season and enters the summer as one of the most coveted players outside the Premier League. He has 12 months remaining on his contract at the Riverside Stadium — a detail that significantly weakens Middlesbrough's negotiating position.
Nottingham Forest manager Vitor Pereira is looking to strengthen in central midfield this summer, in part because of uncertainty over the future of Elliot Anderson. The Portuguese manager's side secured Premier League survival this season after a testing campaign.
Middlesbrough's failure to win promotion through the play-offs makes retaining Hackney considerably harder. The club had hoped promotion revenue — estimated at around £200 million — would give them the financial power to tie the player to a new deal. That opportunity is now gone.
Forest previously attempted to sign Hackney during the January transfer window without success, and are now prepared to act decisively in the summer. Middlesbrough are expected to seek a fee in the region of £25 million, a benchmark set by Alex Scott's move from Bristol City to Bournemouth in 2023.
Hackney contributed five goals and six assists in 39 Championship appearances this season but missed the final weeks of the regular campaign and both play-off legs through injury before making an emotional substitute appearance in the Wembley final. Middlesbrough ultimately fell to a last-minute Hull City goal that extinguished their promotion hopes.
The midfielder is a boyhood Boro supporter but the pull of the Premier League is expected to prove difficult to resist. Boro manager Kim Hellberg was direct about where Hackney's trajectory leads.
"He will end up in the Premier League someday," Hellberg said in March.
Forest are not alone. Tottenham Hotspur, Brentford, Everton, Fulham, Crystal Palace, Brighton and Bournemouth all monitored Hackney closely during the season. Manchester United and Michael Carrick are also reported to hold a genuine interest.
The player who has spent his entire career at Middlesbrough now faces the most significant decision of his professional life.