Match ends, Arsenal 2, Middlesbrough 0.
- Arsenal score twice within two first-half minutes
- Olivier Giroud on 10 for season after brace
- Boro's first shot on target in 39th minute
- Gabriel Paulista makes Arsenal debut
FA Cup holders Arsenal produced an assured display to reach the quarter-finals and end Middlesbrough's impressive run in the competition.
Santi Cazorla split the away side's defence with a through ball for Kieran Gibbs, who squared for Olivier Giroud to steer home the opener.
Giroud added a second with a delightful volley at Boro's near post after slack defending from a corner.
Spanish striker Kike headed against the post late on but Boro created little.
Arsenal, who ended a nine-year trophy drought by winning the FA Cup last season, move into the draw for the last eight as one of five Premier League teams, with League One Preston hosting Manchester United on Monday evening.
Championship Middlesbrough went into the game on the back of six consecutive wins - their best run for 20 years - and 5,280 Boro fans travelled to north London.
New Gunners signing Gabriel Paulista made his debut at centre-back but had little to do as the home side dominated. Albert Adomah's shot, Middlesbrough's first on target, was comfortably saved by Wojciech Szczesny in the 39th minute.
Boro recalled goalkeeper Tomas Mejias, who excelled in the previous round as the Teesside club produced one of the shocks of the season to defeat Premier League champions Manchester City 2-0 at Etihad Stadium, but they could not keep Arsenal at bay.
Cazorla and Gibbs combined for the opener, setting up Giroud whose first-time strike with his left foot went under Meijas.
Just two minutes later Giroud doubled his tally with a beautifully controlled volley at the near post after defender George Friend allowed the Frenchman to escape at Alexis Sanchez's corner.
Middlesbrough managed to shore up their defence in the second half but they remained toothless in attack. Kike's injury-time header was the only time they threatened to score.
And they would have been more heavily beaten had it not been for Mejias, who produced the finest of several good saves when he fell low to his left to tip Sanchez's header round the post.
Boro's focus will now return to their bid for promotion from the Championship, where they can return to the top of the table with a draw at Birmingham on Wednesday.
Arsenal manager Arsene Wenger: "We started well, with a good pace and we controlled the game with our movement and technical quality. We had good team focus overall, we maybe lost our cohesion a little bit at 2-0 but I am happy. Overall we were serious and focused over the whole game.
"Olivier Giroud was very sharp. He has improved a lot compared to the player he was when he arrived here. He is mobile, technically good, and he works with great focus in training. He has become a top player.
"Gabriel Paulista made a great recovery tackle in the box. He wants to defend, he has good urgency levels and a good physique and technical qualities. He is short language-wise but the intelligent players compensate with vision. They look at what their partners are doing, and he did that well."
Middlesbrough manager Aitor Karanka: "It is difficult to play against Arsenal and if you concede goals at set pieces, and if you make mistakes, it is more difficult.
"The way I like to play is to fight but in the first half we did not play in the way I like. We did not fight in the same way as we did against Manchester City and Liverpool. Now we have to think about Birmingham. The league is our objective now."
- 5GabrielBooked at 55mins
- 17SánchezSubstituted forRosickyat 72'minutes
- 23WelbeckSubstituted forWalcottat 72'minutes
- 12GiroudSubstituted forAkpomat 83'minutes
- 23BamfordSubstituted forReachat 54'minutes
- 10TomlinSubstituted forVossenat 54'minutesBooked at 85mins
- Mike Dean
- Shots on Target
Second Half ends, Arsenal 2, Middlesbrough 0.
Corner, Middlesbrough. Conceded by Kieran Gibbs.
Kike (Middlesbrough) hits the left post with a header from the centre of the box. Assisted by Ryan Fredericks with a cross.
Attempt missed. Albert Adomah (Middlesbrough) left footed shot from outside the box misses to the right. Assisted by Jelle Vossen.
Corner, Arsenal. Conceded by Tomás Mejías.
Attempt saved. Theo Walcott (Arsenal) right footed shot from the right side of the box is saved in the centre of the goal. Assisted by Tomas Rosicky with a through ball.
Attempt saved. Mesut Özil (Arsenal) left footed shot from the right side of the box is saved in the bottom right corner. Assisted by Tomas Rosicky.
Jelle Vossen (Middlesbrough) is shown the yellow card.
Santiago Cazorla (Arsenal) wins a free kick in the defensive half.
Foul by Jelle Vossen (Middlesbrough).
Substitution, Arsenal. Chuba Akpom replaces Olivier Giroud.
Offside, Middlesbrough. Ryan Fredericks tries a through ball, but Kike is caught offside.
Attempt blocked. Theo Walcott (Arsenal) left footed shot from the centre of the box is blocked. Assisted by Mesut Özil with a cross.
Mesut Özil (Arsenal) wins a free kick on the left wing.
Foul by Jelle Vossen (Middlesbrough).
Attempt missed. Santiago Cazorla (Arsenal) left footed shot from outside the box is too high. Assisted by Tomas Rosicky following a fast break.
Attempt missed. Adam Clayton (Middlesbrough) right footed shot from outside the box misses to the right following a corner.
Corner, Middlesbrough. Conceded by Gabriel Paulista.
Substitution, Arsenal. Theo Walcott replaces Danny Welbeck.