It was already-relegated Rotherham who did the early pressing with Smith forcing Darren Randolph into a neat stop with a shot across goal.​

Boro's first chance was a good one as Assombalonga snuck through on goal but slipped his effort wide when one-on-one with Lewis Price.​

The visitors' other frontman Ashley Fletcher was the next to take aim but again he did not trouble Price from the edge of the box.​

An even better opportunity fell to Boro defender Ryan Shotton but he headed Lewis Wing's free-kick over when unmarked.​

Smith was then guilty of missing a glaring chance at the other end as he spooned over after Matt Crooks had opened up Boro's defence down the left and squared back for the striker.​

The away side were quick to make them pay when Assombalonga won and scored a 28th-minute penalty after being pulled down in the box by Clark Robertson.​

​The striker should have made it 2-0 moments later as he fired wide after beating the offside trap.​

Middlesbrough did not to wait too much longer to double their lead, though, with Mikel netting in the 37th minute.

The ball fell to the Boro skipper from a corner and he viciously lashed it into the roof of the net through a crowd of bodies.​

​Mo Besic could have made the points even more secure in the second half after he latched onto a loose ball from Semi Ajayi and powered towards goal, only to fire over from the edge of the box.​

Rotherham continued to have a go and it took a brave block from George Saville to deny Joe Newell from inside the box following a good move.​​

Ajayi then rose highest from a corner but his header was incredibly clawed out by Randolph.​

Millers substitute Kyle Vassell was the next to come close as he burst down the left and his poked shot was kicked away by Randolph.​

​Vassell came even closer moments later as he muscled his way through before unleashing a fierce strike which rattled the woodwork.​

​And it was Vassell in the thick of it again in the 86th minute, winning Rotherham a penalty after he was tripped by Mikel when he was about to pull the trigger.​

​Smith stepped up and finally beat Randolph from the spot with a cool finish, but Rotherham were unable to find an equaliser at the end of a match which saw both sides suffer disappointment.

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