Tony McMahon has signed a new one-year contract with Middlesbrough, while Tom Craddock and Joe Bennett have also committed their foreseeable futures to the club.
McMahon, a product of Boro's youth system, was offered a new deal late last year but chose to keep his options open.
But the 22-year-old has now inked fresh terms with the club as he looks to get his career at the Riverside back on track after recent injury troubles.
Craddock, another product of Boro's youth set-up, has also put pen-to-paper on a 12-month deal.
Meanwhile, Bennett, 18, has been rewarded with a two-year contract after showing signs of promise for the reserves last season.