Boro brought in goalkeeper Jordan Archer, Darnell Fisher, Yannick Bolasie, Nathaniel Mendez-Laing and Neeskens Kebano to bolster their squad as they push for a play-off place in the Championship.
The Teessiders have also welcomed back defender Grant Hall and striker Ashley Fletcher from injury – so who will start when everyone is fit and available?
Obviously there will be more injury setbacks before the end of the campaign, and Warnock will choose to alter his side and formation depending on the identity of the opposition.
Still, we’ve put together what we think could be Boro’s strongest starting XI, and substitutes bench, when everyone is fit.
Scroll down and flick through the pages of our picture gallery to see if you agree:
13. Sub: Grant Hall
Will hopefully be able to stay fit after suffering multiple injury setbacks. Boro are short of cover at centre-back after allowing Nathan Wood to leave on loan. Photo: PA
14. Sub: Darnell Fisher
Produced an excellent performance on his Boro debut at Norwich. Will provide competition at full-back during the second half of the campaign. Photo: Stephen Pond
15. Sub: Sam Morsy
Gives the side extra security when he plays alongside Saville and Howson in midfield. Morsy has shown other qualities in his game aside from his defensive attributes, yet there is now more competition in the squad. Photo: Getty Images
16. Sub: Marvin Johnson
Has been a regular this season after signing a one-year contract extension in the summer. The winger has also responded well after dropping out of the side. Photo: George Wood