Midfielder Lewis Wing impressed during the 2018/18 campaign.
Our reporter Joe Nicholson has selected his 11 best players based on their seasons from start to finish - scroll down and flick through our gallery to see the results:
Flint struggled at times during a difficult campaign but was still part of the best defence in the Championship, making 39 league appearances for the Teessiders.
The winger didn't feature for a prolonged spell in the second half of the season due to a clause in his contract. Yet Downing was one of Boro's best performers in the first half of the campaign in a side which lacked creativity.
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It was a stop-start season for the combative midfielder. Even so, Clatyon still produced some standout displays, particularly in the first half of the campaign, to protect Boro's defence.
Mikel slotted straight into midfield, at Clayton's expense, and showed his top-flight experience after joining Boro in January.
Shotton's versatility proved valuable for Boro throughout the campaign, as the 30-year-old switched from wing-back and centre-half - sometimes in the middle of games.
Despite his red cards against Sheffield United and Preston, Ayala was still a vital cog in Boro's well-drilled backline. His winning goal against West Brom in August was also particularly memorable.
Boro were the lowest scorers in the top half of the Championship , yet Assombalonga still netted 16 goals in all competitions. That's seven more than any of his team-mates.
Wing was a revelation in Boro's midfielder after breaking into the side at the end of 2018. With the Teessiders struggling for goals, the midfielder added some much-needed creativity in the engine room.
The 21-year-old centre-back went from strength to strength, stepping up to become a key player for manager Tony Pulis. An injury to Fry late in the campaign was a big blow.
The energetic midfielder was asked to play all over the park this season, always giving 110 per cent. Howson featured in all 46 of Boro's league games, performing consistently throughout the campaign.
One can only imagine where Boro would have ended up without their impressive shot-stopper. Randolph saved the Teessiders several points throughout the campaign.