Arsenal are through to the semi-finals of the EFL Cup courtesy of a scrappy 1-0 win over West Ham United at the Emirates Stadium this evening.

The Gunners looked disjointed throughout but just about deserved their victory, scoring through the game's only shot on target after Danny Welbeck bundled home his first goal in the competition since October 2009.

There was some bad news for Arsenal, however, as back-up striker Olivier Giroud hobbled off late on with what appeared to be a hamstring injury, likely ruling him out of his side's festive fixtures.

A deflected Welbeck shot, which ended well wide of the target, was the only attacking moment of note in an extremely flat opening half-hour to the contest, setting the tone for what was to follow.

The game struggled to flow due to a number of sloppy passes, not helped by the combined 17 changes made to the starting lineups - a full 11 of those by Arsenal.

With eight minutes of the first half to go the hosts finally managed to wake up, as Sead Kolasinac cut in from the left and blasted one over, before setting up Theo Walcott for what looked certain to be the opener.

Walcott was completely unmarked when meeting the ball with his head 12 yards out, but he could not steer it on Joe Hart's goal.

The Gunners did not have to wait too much longer for their breakthrough moment, though, thanks to a close-range finish from Welbeck under the crossbar after Mathieu Debuchy nodded the ball into a dangerous position.

Joe Willock was unable to keep his composure from the next opening, sending a shot into the stands from the edge of the area as Arsenal took a slender lead into the break.

There was also a flat feel to the second half, which was delayed by five minutes due to a change of linesman as fourth official Chris Kavanagh took over from the injured Stuart Burt.

With a little over an hour played Aaron Cresswell curled a free kick wide, marking West Ham's first attempt of any note, and that provided the signal for David Moyes to throw on Andy Carroll and Diafra Sakho.

Hart, back between the sticks after a four-game absence, brought down Welbeck 14 minutes from time just outside the box and was glad to see referee Kevin Friend show only a yellow card.

A forgettable game drifted to its conclusion, meaning a 15th last-four appearance for Arsenal and a first in seven years.

Arsenal XI: Ospina; Debuchy, Chambers, Holding, Kolasinac; Coquelin (Dasilva 90'), Elneny; Willock (Sheaf 84'), Walcott, Welbeck; Giroud (Nelson 77')

West Ham United XI: Hart; Masuaku; Reid, Collins, Ogbonna, Cresswell (Carroll 65'); Rice, Obiang, Quina (Arnautovic 83'); Ayew, Chicharito (Sakho 65')