Neil Warnock’s men were made to work for victory against a side who defended with 10 men behind the ball for long periods and were tough to break down.  

The victory also extended the unbeaten run to seven games and lifts the team to seventh in the Championship, the highest league position in over 18 months. 

It was game where Boro dominated possession and territorial advantage, while Coventry parked the bus.  

The pattern for the game as set early on when Sam Morsy hammered a shot wide of the mark after Coventry goalkeeper Marko Marosi had fumbled a low ball drilled into the box from Marcus Tavernier. Marosi failed to hold a Tavernier shot later in the first half but the ball was scrambled to safety by the visitors. 

Jonny Howson also sent a shot over from outside of the area while Patrick Roberts followed suit moments later after capitalising on some sloppy play by the visitors. 

When Boro did manage to break down the Sky Blue wall, goalkeeper Marosi looked vulnerable and it was after another fumble that Morsy saw his powerful shot deflected onto the cross bar. The keeper also fumbled another shot from Tavernier, but recovered at the second attempt with Assombalonga waiting to pounce. 

On the rare occasions the visitors threatened Dael Fry made a good block and reacted well to clear the danger, while Marcus Bettinelli had just one comfortable save to make. 

Hayden Coulson and Marcus Browne were introduced as Warnock looked to his Boro side to find a way past their dogged opponents. George Saville was denied by some good defending after an excellent ball from Jonny Howson, and Assombalonga headed over when presented with an opportunity. 

It was threatening to be a frustrating evening for Boro, but the decisive goal came with 10 minutes left on the clock. Morsy was the architect with a ball through the defence and Assombalonga, who still had it all to do, showed good strength and composure before tucking the ball home.

Assombalonga’s first goal of the season looked like being enough, but in the six minutes of added time, there was another first goal of the campaign, for Spence, who raced clear on the right before drilling the ball home to put the seal on the win.