Last updated on .From the section Championship

Britt Assombalonga opened his account for the season with a first-half effort

Promotion favourites Middlesbrough continued their unbeaten start to the season with a comfortable win against Birmingham City, who had Craig Gardner sent off late on.

Britt Assombalonga's first-half curler, bent beyond Connal Trueman from a pass by Jonny Howson, was the Teessiders' only goal, despite numerous chances to add to the tally.

Assombalonga could have followed that up by claiming a hat-trick - but struck the post and was unable to convert Ryan Shotton's dangerous throw - while winger Stuart Downing also hit the woodwork from a free-kick.

Chances were difficult to come by for the visitors, former Blues keeper Darren Randolph denying Che Adams and Lukas Jutkiewicz before Gardner's dismissal for a late lunge on Howson ended their hopes of a fightback.

Defeat made for a difficult return to Teesside for former Boro boss Garry Monk, who lost his opening game in charge of Birmingham against his old employers and saw his side struggle to impose themselves at the Riverside.

Transfer window arrivals Omar Bogle and Connor Mahoney were given their debuts off the bench, although their late cameos were unable to turn the game around.

The past week has been a mixed one for Monk's Middlesbrough counterpart Tony Pulis, with the departure of Adama Traore and Ben Gibson offset by the loan arrival of striker Jordan Hugill from West Ham United.

With that added competition in the ranks it was the perfect time for former Nottingham Forest striker Assombalonga to remind his manager of his talents, scoring his first goal of the season before making way late on for Ashley Fletcher.

Middlesbrough boss Tony Pulis told BBC Tees:

"They've been fantastic, the lads today, when you think it's the third game in a week, and conditions on the three games were very warm and very humid.

"And let's be fair: we should have won the game by five or six goals. It's an absolute travesty that the game has finished 1-0.

"The lads certainly deserved it. Some of the football that we played to create the opportunities and chances was absolutely first-class, and you have to put them away when you're creating them."

Birmingham City boss Garry Monk said:

"This is a league that demands you be on your game from the start, especially away from home against one of the better teams. In the first half, we were not.

"We caused our own problems. It was 1-0 and they could have maybe scored another.

"We were much better in the second half, without being at our best, but it is very early days. We have new players and we will get better. The fighting spirit is there but we made it too easy for them in the first half."