The result means the Bees are up and running after losing their opening game of the season to Birmingham, but leaves new Middlesbrough head coach Jonathan Woodgate still searching for his first victory.

It didn't look like that would be the case for most of the first half, but while Boro had the ball in the net on two separate occasions before the interval, both efforts were struck off by the officials.

The first decision was by far the most contentious, with some smart thinking from Marvin Johnson catching Brentford goalkeeper David Raya badly out of position from a quickly-taken corner.

Raya flapped at the ball as he tried to scramble back into the six-yard box, but while Ashley Fletcher bundled home from close range, the Middlesbrough striker was adjudged to have used his arm.

Fletcher was celebrating again 15 minutes later, but while he lofted home a lobbed finish after racing on to Daniel Ayala's through ball, the offside flag had already been raised.

Brentford spent most of the opening period trying to contain Boro's attacking threat, and Raya was forced into a fine save five minutes before the interval, tipping Johnson's shot around a post after the winger dispossessed Ethan Pinnock.

Three minutes later and Boro were going close again. Adam Clayton released Assombalonga into the left of the box, but while the striker's low shot beat Raya from an acute angle, the ball rebounded off the base of the left-hand post.

Brentford barely made it into their opponents' half before the break, but the visitors were a different proposition at the start of the second half.

Emiliano Marcondes teed-up Mathias Jensen on the left-hand side of the area and the midfielder fired in a fierce strike that Darren Randolph parried away to his left.

Henrik Dalsgaard fired in a shot that deflected over off a sliding Hayden Coulson, and with the complexion of the game having changed completely, the visitors claimed the lead nine minutes into the second period.

Canos beat Ayala as he broke down the right-hand side, and after the Spaniard delivered a low ball into the six-yard box, Watkins was left with the simple task of slotting home from close range.