Arsenal 2 Middlesbrough 0

Olivier Giroud netted twice in the space of three minutes as Arsenal overcame promotion-chasing Middlesbrough to book their place in the FA Cup quarter-finals.

Giroud put the holders ahead in the 27th minute and then doubled their advantage almost immediately with a classy left-foot volley to kill off Middlesbrough’s hopes of an upset.

Arsenal made all the running from the start, but they were kept at bay by Boro goalkeeper Tomas Mejias, who sprang to push Santi Cazorla’s dipping free-kick behind.

Mejias also smothered a surge from the overlapping Kieran Gibbs and clawed away Giroud’s left-foot drive, while Kenneth Omeruo came to the visitors’ rescue with Alexis Sanchez poised to pull the trigger.

However, the breakthrough finally arrived when Cazorla threaded a pass wide for Gibbs and the left-back’s low cross was tucked in first time by Giroud.

And the Frenchman doubled his tally two minutes later, with Kike slow to react as Sanchez dispatched a corner to the near post, allowing Giroud to get across him and whip the volley beyond Mejias.

Sanchez seemed set to make it 3-0 as he played a one-two with Mesut Ozil and evaded Mejias, but Adam Clayton got back to clear the ball off the line.

It wasn’t until six minutes before half-time that the Teessiders finally mustered a shot at goal, Albert Adomah bursting through to bring a low stop from Wojciech Szczesny.

Arsenal’s 2-0 lead at half-time looked a comfortable one – as it had done against Leicester in midweek – but there was never any danger of a repeat bout of complacency.

Mathieu Flamini and Danny Welbeck both had opportunities to extend the Gunners’ lead, while Ozil gave Omeruo the slip and thumped a shot that was beaten away by Mejias.

The keeper also tipped over a ferocious drive from Gibbs and produced a magnificent save low to his left to prevent a glancing header by Sanchez crossing the line.

Cazorla might have capped his impressive display with a goal 14 minutes from time, but he speared the chance over the bar after a break involving Giroud and substitute Tomas Rosicky.

Another Arsenal replacement, Theo Walcott, should also have increased his side’s advantage late on when he raced onto Cazorla’s pass, only to be denied by Mejias at close range.

At the other end, Kike almost pulled back a consolation goal, heading Ryan Fredericks’ cross against the post – but it would have made little difference as Arsenal eased a step closer to a Wembley return.

Arsenal: Szczesny; Chambers, Gabriel, Koscielny, Gibbs; Cazorla, Flamini; Sanchez (Rosicky 72), Ozil, Welbeck (Walcott 72); Giroud (Akpom 83).