Middlesbrough may have run riot in defeating Peterborough in the FA Cup but their prolific goalscoring form deserted them in a blood-and-thunder start.

There was little attacking menace in the first 20 minutes as they found Birmingham to be in combative form and more than holding their own against a top-six side.

When Boro discovered a way through Birmingham's rearguard, Jordan Hugill made a hash of the opportunity. George Saville set up the opening but Hugill miserably misfired well wide from a very good position.

The on-loan West Ham striker could not be faulted for effort and he gave Michael Morrison and Harlee Dean a torrid time in an attempt to break the deadlock.

He came in for some heavy treatment from the Birmingham defenders and as a result referee Graham Scott was questioned by Boro skipper, George Friend.

Almost immediately Birmingham's Maikel Kieftenbeld collected the first booking of the game for a rash tackle on Mo Besic as the game suddenly became more physical.

A fired-up Hugill then had a shot knocked down and Dael Fry latched onto the loose ball only to see Kristian Pedersen block his effort on the line.

This concentrated pressure finally paid a rich dividend for Boro when Saville's cross from the right was tapped in at the far post by Wing for his third goal of the season.

Nine minutes into the second half there was a controversial incident when Adams appeared to be tripped in the penalty area only for the referee to book the Birmingham player for diving.

The game continued to be played at a frantic pace with a catalogue of infringements as Boro desperately
held onto their slender lead.

Only the woodwork saved Boro in the 60th minute when Dean's close range header from a Jota free-kick on the right crashed against the post.

With Birmingham striving for an equaliser Darren Randolph had to show some international form to save a Lukas Jutkiewicz blockbuster through a crowded Middlesbrough defence.

In an end-to-end encounter Birmingham deservedly levelled the score in the 79th minute when Adams played a one-two with Jutkiewicz and fired home a raking drive past Randolph.

But Birmingham's joy was shortlived as Assombalonga, who had replaced Hugill, scored a breakaway goal in the 82nd minute.

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