Marvin Johnson, who was preferred to fellow forward Stephen Walker, drove down the right-hand side in the opening five minutes, but while his cross fell invitingly for Hayden Coulson, the young full-back was unable to find the target with a drive that sailed over the crossbar.

Daniel Ayala also threatened in the opening stages, but while the centre-half rose effectively to meet Marcus Tavernier's free-kick at the back post, he was also unable to test Huddersfield goalkeeper Kamil Grabara.

Huddersfield's players gradually grew into the game, but the visitors' first opportunity came to nothing midway through the first half when Steve Mounie headed Karlan Grant's corner wide of the target at the back post.

Grant thought he should have had a penalty midway through the opening period, but referee Darren England waved away the striker's appeals after he was brushed aside by Ayala.

Huddersfield's frustrations increased eight minutes before the break, as Middlesbrough claimed the lead courtesy of one of the best passing moves of the game.

Tavernier released Ashley Fletcher into the left of the box, he slid a low cross across the face of the six-yard box, and an unmarked Spence swooped to slot home his first senior goal. Still just 19, the wing-back has made four Championship appearances since stepping up to the first team.

Huddersfield improved as they looked for an equaliser at the start of the second half, but Jon Gorenc-Stankovic passed up a glorious chance of a leveller shortly before the hour mark.

The defender was four yards out when he rose to meet Juninho Bacuna's corner, but his header sailed harmlessly over the bar.

Huddersfield wasted another excellent opportunity four minutes later, with Mounie replacing Stankovic as the guilty party inside the six-yard box.

The striker looked certain to score when Ayala and Jonny Howson both failed to cut out Elias Kachunga's cross, but he rushed his shot and blazed wastefully over.

Coulson and Fletcher wasted late chances to make things safe for Middlesbrough – the former failed to convert Spence's cross while the latter shot straight at Grabara when well-placed.