In a fiercely-fought contest at the Riverside Stadium, that saw Neil Warnock's side dominate possession and take ten shots to the visitors' two, Paddy McNair's 82nd minute goal secured a draw for his side and ended the Bluebirds' relentless six-game winning streak.
Speaking after the game, Boro's boss was quizzed on the fitness of his January signings, and he claimed: "He (Nathaniel Mendez-Laing) will get sharper. He has been out a long time really. That’s the same with (Neeskens) Kebano really, he hasn’t had much football.
"Yannick (Bolasie) hasn’t either, and if you had seen him on the training ground yesterday…they told me he wasn’t fit as well.
“I think I am in the wrong game. They say he has to do longer sprints, longer runs. Hopefully he will be available at some stage before next weekend I hope.”
Middlesbrough are back in action tomorrow evening, when they travel to take on Coventry City at St. Andrew's.
Here are today's biggest transfer stories and the latest team news involving Middlesbrough and the rest of the Championship, ahead of the midweek action:
9. Rhodes tipped to leave Owls this summer
Sheffield Wednesday's record signing, Jordan Rhodes, has been tipped to join Cardiff City at the end of the season, once his contract expires. He joined the Owls for £10m from Middlesbrough back in 2017, and has scored just 13 goals. (The Sun) Photo: Michael Regan
10. Rovers striker could cost £25m
Blackburn Rovers are set to demand a fee in the region of £25m for star striker Adam Armstrong this summer, mindful of fact his former club Newcastle will pocket 40% of the sell-on fee. He's a key target of West Ham United. (Daily Mail) Photo: Laurence Griffiths