It has been known for some time that striker duo Britt Assombalonga and Ashley Fletcher will both leave this summer, while goalkeeper Jordan Archer, Nathaniel Mendez-Laing and Marvin Johnson won’t be offered new deals either.
It leaves the Teessiders needing to fill several positions during the transfer window, and manager Neil Warnock has previously said he wants to sign around eight or nine new players.
Boro have also seen a handful of loan players leave the Riverside, including Yannick Bolasie, Neeskens Kebano and goalkeeper Marcus Bettinelli.
The Teessiders have at least confirmed that Joe Lumley will join the club from QPR when his contract expires at Rangers in July.
Following the recent departures, we’ve put together Boro’s strongest starting XI and subs bench as things stand.
1. GK: Joe Lumley
The Teessiders moved quickly to sign the 26-year-old, who will officially become a Boro player at the start of July when his QPR contract expires. Lumley will be hoping to establish himself as the club's No 1 keeper. Photo: Getty Images
2. RB: Anfernee Dijksteel
After missing the end of last season with an ankle injury, the 24-year-old Dutchman will be hoping to build on his impressive 2020/21 campaign following a strong pre-season. Photo: George Wood
3. CB: Grant Hall
A commanding centre-back who looks set to play a key part next season. Hall was unfortunate with injuries during the first half of the 2020/21 season but performed well during the second half of the campaign. Photo: Stu Forster
4. CB: Dael Fry
Warnock believes Fry is the best centre-back in the Championship. The 23-year-old was forming a fine partnership with Hall before suffering an injury setback in April. Photo: Getty Images