Ljungberg and Lauren celebrate Henry's opener
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Thierry Henry, Robert Pires and a late brace from Dennis Bergkamp sent Arsenal on their way - and made it a miserable start to the season for Middlesbrough's new manager Steve McLaren.
Much had been made of Arsenal's poor away from last season - but they silenced their critics in emphatic style at The Riverside.
Then subsitute Bergkamp took over with two goals in as many minutes in injury time.
The only sour note of a well-contested game were the second-half dismissals of Ray Parlour and Ugo Ehiogu.
Arsenal nearly took the lead as early as the second minute.
Pires knocked over a cross from the right wing and Tony Adams, up for a free-kick seconds earlier, headed for goal, only to see Ehiogu deflect the ball over with his head.
Windass had Middlesbrough's best chance of the game, when he beat the Arsenal offside trap only to shoot over from ten yards.
More good work down the Arsenal right saw Pires sent clear into the Middlesbrough - but his effort went straight into Schwarzer's body and the goalkeeper scrambled to
hold on.
Parlour became the first player to have his name taken for a hard challenge on Dean Windass.
Arsenal finally made the breakthrough they deserved when a cross from the right fell into Henry's path courtesy of an Ehiogu header which deflected off Mustoe.
Parlour off
Henry chested the ball instantly and struck a perfect volley into the corner.
Parlour's earlier yellow card became more relevant when he was cautioned again for a late challenge on Ehiogu and was given his marching orders.
After 10 minutes of the second half, Windass was replaced by Hamilton Ricard.
The change invigorated Boro, who came closer than before with Ince's left-footed daisy-cutter which forced Seaman into an excellent one-handed save to his right.
Neither team threatened much until the penalty awarded to Arsenal five minutes from time.
According to referee Graham Barber, Ashley Cole was tripped by Ehiogu, who was promptly shown the red card.
Replays suggested any contact was minimal and that Cole may have dived.
Pires slotted away the penalty before Bergkamp took over with a late brace.
The first came from a move down the left, with Cole threading a pass through to the Dutchman who stroked home from close range.
His second was very similar, with Pires again instrumental and Bergkamp calmly finishing with his left foot.
Middlesbrough: Schwarzer, Fleming, Cooper, Southgate, Ehiogu, Ince, Mustoe, Greening, Windass, Boksic, Job. Subs: Crossley, Vickers, Okon, Wilson, Ricard.
Arsenal: Seaman, Cole, Adams, Campbell, Vieira, Pires, Ljungberg, Lauren, Parlour, Wiltord, Henry. Subs: Jeffers, Bergkamp, van Bronckhorst, Grimandi, Wright.
Referee: G Barber (Tring).