Boro find themselves in the thick of the transfer gossip at the moment as the Djed Spence saga continues.
The future of Spence may determine how much Boro boss Chris Wilder can spend this summer as speculation linking the defender with a move to Tottenham Hotspur or Nottingham Forest continues.
Boro themselves have already been linked with several players this summer including Premier League youngsters Cameron Archer and Aji Alese.
Boss Wilder is believed to be interested in bringing in a goalkeeper this summer as well as strengthening his attacking options but what free agents should the Teessiders be considering?
As players up and down the country get set for their release from clubs at the end of the month, we look at some of those heading out of contract who could be of interest to Boro this summer.
1. John Ruddy
The experienced goalkeeper leaves Wolverhampton Wanderers after five years at Molineux this summer and could bring some much needed stability to a problematic area for Boro. (Photo by Nathan Stirk/Getty Images) Photo: Nathan Stirk
2. Alex Smithies
It's no secret Boro are searching for potential goalkeepers this summer and Smithies is someone who could be considered following his exit from Cardiff City. The 32-year-old made over 30 appearances for the Bluebirds last season after a £3.5million switch from QPR in 2018. (Photo by Dan Istitene/Getty Images) Photo: Dan Istitene
3. Sam Johnstone
At this stage it would take an impressive offer from Boro to convince Johnstone to remain in the Championship with reports suggesting the ex-West Bromwich Albion stopper is set to sign for Premier League side Crystal Palace. But until a deal is done, it's never quite done. (Photo by Naomi Baker/Getty Images) Photo: Naomi Baker
4. Ryan Fredericks
With the anticipated exit of Djed Spence, the fullback area is somewhere Boro boss Chris Wilder could target. Fredericks would certainly fit that bill and would be in familiar surroundings after spending the 2014/15 season at the Riverside. The 29-year-old is another who may be close to a Premier League move however with newly promoted Bournemouth said to be close to a deal. (Photo by Glyn KIRK / AFP) (Photo by GLYN KIRK/AFP via Getty Images) Photo: GLYN KIRK