Henry's treble saw him equal Cliff Bastin's Arsenal record of 150 league goals and Philippe Senderos, Robert Pires, Gilberto Silva and Alexander Hleb were also on target against 10-man Middlesbrough.

Arsene Wenger's side played with a verve and freedom that has often been missing in this campaign as they ran up their biggest win since they beat Everton by the same score at the end of last season.

Arsenal had been held scoreless in their last two Premiership matches but they started in determined mood and quickly had Middlesbrough on the back foot.

Henry came close to making the breakthrough in the 12th minute when he curled a ferocious free-kick just past the post.

There was little respite for Middlesbroughs over-worked defenders as Arsenal took control in the early stages and Henry should have done better than direct a header over from close range.

It seemed inevitable that McClaren's side would crack under the weight of Arsenal's pressure and so it proved in the 20th minute.

Freddie Ljungberg found space down right and his cross from the goal-line was met by Henry with an exquisite volley that gave Brad Jones no chance.

Arsenal surged forward straight from the re-start and Cesc Fabregas saw his drive turned away by Jones.

Senderos then took advantage of slack marking from the resulting corner as he powered a header past Jones for his second goal of the season.

Henry was virtually unstoppable by now and scored his second after half an hour. He burst clear of teenage defender Matthew Bates and calmly slotted a low shot past Jones.

Arsenal weren't finished yet and on the stroke of half-time Pires piled on the misery for Middlesbrough when he cut in from the right and bent a superb shot into the top corner.

Gilberto Silva scored the fifth after the interval when he met Henry's free-kick with a powerful header from 10 yards.

And Henry completed a majestic hat-trick when he placed a precise shot beyond the beleaguered Jones from close range.

Middlesbrough, now without a win in eight Premiership matches, were suffering an afternoon to forget and it got worse when Brazilian midfielder Doriva was dismissed after earning a second yellow card for a tug on Henry.

Hleb came off the bench to make it seven in the final minutes when he tapped in his first Gunners goal after Middlesbrough's defence was destroyed by yet another flowing Arsenal move.

In the battle between Liverpool and fourth-placed Tottenham at Anfield, Australia star Harry Kewell's first home goal since 2003 was decisive.

Everton pulled away from danger with a 1-0 win away to drop candidates Portsmouth while Charlton enjoyed a morale-boosting 2-0 win over second-bottom Birmingham City.

West Ham came from behind to beat Aston Villa 2-1 and Fulham defeated Newcastle 1-0 thanks to a 75th minute goal from Steed Malbranque.