Boro have made 11 signings, both loan and permanent deals, over the past 12 months as Neil Warnock’s side pushed for a play-off place in the Championship.
After a strong start to the season, the Teessiders’ promotion hopes slowly faded as Neil Warnock’s side eventually finished 10th in the table.
Boro made five new additions during last summer’s extended transfer window, while Duncan Watmore later joined on a free transfer in November.
Warnock was able to bring in five more players in January as he looked to strengthen his squad, yet multiple injury setbacks also cost his side towards the end of the campaign.
Here, our Boro writer Joe Nicholson has rated each Boro signing from the 2020/21 campaign based on the deal and players’ performances.
1. Grant Hall - 7
It looked like it was going to be a tough first season at Boro for the former QPR captain. But after a tough spell with injuries, the 29-year-old centre-back was excellent in the second half of the campaign. On a free transfer, the signing looks like a shrewd piece of business. 7 Photo: Stu Forster
2. Marcus Bettinelli - 5
The Fulham goalkeeper appeared to be what Boro needed at the start of the season - a vocal presence who had previously won promotion from the second tier. Yet despite Boro's impressive defensive record in the first few weeks of the campaign, Bettinelli made some costly mistakes as the Teessiders' drifted away from the play-off pack. 5 Photo: Alex Burstow
3. Sam Morsy - 8
Morsy wasn't Boro's first choice heading into last summer's transfer window but the 29-year-old has certainly been a fine capture after arriving from Wigan. The former Latics skipper appears to be one of the few natural leaders in the Boro squad. 8 Photo: Catherine Ivill
4. Chuba Akpom - 4
After a promising start, scoring in his first two Boro appearances, Akpom struggled in his first season at the club following his permanent transfer from Greek side PAOK. The 25-year-old didn't appear to suit the Teessiders' system and finished with five goals in 38 games. 4 Photo: Getty Images