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:
17. Sub: Marcus Tavernier
It seems harsh to leave the midfielder out of the starting XI given that he's enjoyed a fine season so far. The 21-year-old will have to force his way back into the side when he returns from injury but has been going from strength to strength this campaign. Photo: Alex Burstow
18. Sub: Nathaniel Mendez-Laing
Warnock has admitted it will take a few weeks for the winger to get up to speed. Mendez-Laing has excelled under the Boro boss at Cardiff and could be a real asset if he rediscovered his old form. Photo: MFC
19. Sub: Chuba Akpom
The striker's performances have been a bit hit and miss after he joined Boro in the summer. He should perform better with more attack-minded players around him. Photo: Getty Images
20. Sub: Ashley Fletcher
The striker was Boro's top scorer last season and has returned to action after suffering a hamstring injury in September. He could be like a new signing up front. Photo: Jan Kruger