Arsenal's young guns - eager to impress boss Arsene Wenger - turned on the style to dump United from the Carling Cup.

Despite making wholesale changes from their Premiership squad, the Gunners included five full internationals in their line-up and between them Dane Nicklas Bendtner and Mexican Carlos Vela netted five of the six goals.

Exactly two years to the day after United's Premiership visit to the Emirates Stadium,
the travelling contingent again had little to cheer as the Blades slipped to the club's heaviest League Cup defeat.

Boss Blackwell resisted the temptation to make wholesale changes, as he has done in the previous rounds of the competition. From Saturday's encounter at Norwich, he made just one change with Webber replacing Sharp in attack. Wenger, meanwhile, decided to continue his policy to blood Arsenal's highly-respected youngsters in the third round fixture.

In a subdued start it appeared that United had opted for a 4-3-3 formation with Webber and Cotterill flanking Beattie in attack. The visitors delivered the first cross and also won the night's first corner, on eight minutes.

Speed's pass, on 11 minutes, allowed Webber to use his pace and cut in from the left, beating three defenders, but he lacked composure with his finish. Arsenal, as ever, looked calm with the ball at their feet and continually found their targets with passes. From Randall's first corner, Kenny was a full stretch to tip away.

Randall also curled a free-kick just over the angle on 22 minutes and Kenny was forced to parry away from Djourou after the central defender had made an impromptu burst into the Blades penalty area.

The first time that Arsenal's youngsters showed any inexperience was in the 30th minute when Wilshere fired well wide after Bendtner's clever flick on presented a chance, but the home side took the lead soon after. Vela held off Morgan and found BENDTNER, who perfectly passed the ball into the net from 25 yards, beyond Kenny's left hand.

There were appeals for a penalty when Wilshere went down after Morgan's challenge before Arsenal added a second. Ramsey confidently held on to position and with a neat back heel found BENDTNER, who beat the offside trap before slipping the ball under Kenny's body.

There was little time for United to digest the goal before a third arrived two minutes later. This time Bendtner turned provider, sliding a pass through to VELA, who also beat the offside trap before curling into the corner of Kenny's net.

Before the break there was time for a United chance but after Quinn and Beattie eased the ball to the right, Cotterill cut in onto his left foot before curling just wide of Fabianski's post.

It was Cotterill's final contribution as he was replaced by youngster Naughton at the break but Arsenal began the second period as they had left off in the first and Kenny was forced to claw away a Gibbs shot.

Just five minutes of the second half had elapsed when Arsenal added a fourth. Gibbs sent a forward ball down the left channel where VELA was waiting to beat Morgan before dinking a clever shot over the head of Kenny.

Before the hour mark, Arsenal went nap. United were caught cold from a corner routine and WILSHERE was given enough time to pick his spot in the bottom corner, despite Kenny getting a hand to the ball.

In a rare Blades attack, Morgan connected with Halford's long throw but could not trouble Fabianski before Arsenal returned to the ascendancy. Djourou headed over and Bendtner wasted a great chance to complete his hat-trick after Merida's pass.

Kilgallon forced Vela wide as the Mexican looked for his hat-trick and Lansbury and Ramsey both had shots on Kenny's goal.

At the other end, Quinn's effort was blocked after Beattie headed down Naysmith's cross and Webber fired over, whilst Blackwell gave valuable big-match experience to Sheffield-born youngster Robertson.

The impressive Vela completed the scoring with his hat-trick on 87 minutes. Ramsey spotted VELA in the left channel and the striker smashed another powerful shot under the hapless Kenny.

Two minutes of injury-time was too much and a tired-looking United team trudged from the pitch at the final whistle.

Arsenal: Fabianski, Vela, Ramsey, Song (Lansbury 71), Wilshere, Djourou, Bendtner (Simpson 71), Gibbs, Hoyte, Merida (Coquelin 71), Randall.
Unused: Mannone, Emmanuel-Thomas, Ogogo, Frimpong.

Blades: Kenny, Halford, Naysmith, Cotterill (Naughton 45), Morgan, Kilgallon, Beattie (Robertson 77), Webber, Speed (Hendrie 73), Montgomery, Quinn.
Unused: Bennett, Sharp, Geary, Ehiogu.