George Friend and Jonny Howson were both set to undergo minor surgery today.
The club captain was due for a procedure on a ruptured tendon while Howson has a hernia.
Rudy Gestede suffered a hamstring injury during training while on international duty with Benin and is undergoing treatment.
Hayden Coulson, who has been sidelined since the game against Brentford in August, is making progress while Dani Ayala, who missed the trip to Bristol City last time out, has returned to training.
|Next up at the Riverside...
Boro v Reading
Saturday 14 September. KO 3pm
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