Jay Simpson scored twice as Arsenal's youngsters put on a fine display to beat Wigan 3-0 in their Carling Cup fourth-round clash at the Emirates Stadium.
Simpson scored either side of half-time in his first start for the club to embarrass their Premier League counterparts in an entertaining encounter.
The 19-year-old broke the deadlock four minutes before the break when he picked up a Carlos Vela through-ball to neatly chip the ball over the on-rushing Chris Kirkland to score his first goal for the club.
Poor defending from Titus Bramble on 66 minutes allowed Vela to sneak behind the Latics defence and square the ball to Simpson who slotted past Kirkland for his second.
Four minutes later the Mexican got himself on the scoresheet when he raced through to latch onto a Johan Djourou pass and chip over Kirkland from the edge of the box to seal the win.
Manchester United had to rely on a second-half penalty from Carlos Tevez to squeeze past stubborn QPR at Old Trafford.
Sir Alex Ferguson made eight changes from the side that lost to Arsenal at the weekend and the youthful side failed to get into their rhythm early on.
Rangers frustrated United for the majority of the first half and the Premier League champions went in at the break goalless after missing chances through Tevez and Nani.
After laying siege to the QPR goal in the second half, United finally breached the Rangers defence 15 minutes from the end when Tevez struck from the spot after Peter Ramage had hacked down second-half substitute Danny Welbeck.
A first-half double strike ensured Derby overcame League One outfit Leeds 2-1 at Pride Park.
Paul Jewell's side took the lead after just five minutes when Emanuel Villa clipped a curling left-foot shot past Casper Ankergren to pick up his fifth goal in four.
The hosts doubled their lead 13 minutes later when Nathan Ellington coolly slotted home after some good work by Villa and Kris Commons.
Leeds clawed themselves back into the game with a Luciano Becchio header seven minutes before the break but despite applying some second-half pressure, they could not find an equaliser.
Goals from Glenn Whelan and Danny Pugh gave Stoke a 2-0 win over a spirited Rotherham side at the Britannia Stadium.
Whelan fired home a dipping 20-yard free-kick 20 minutes in to put Stoke into the lead before Pugh doubled the hosts' advantage with a cool finish from Dave Kitson's pass just before the hour.
Reuben Reid and Drewe Broughton threatened for the League Two visitors in the second half but Stoke comfortably held on to seal their passage to the quarter-finals.
Managerless Watford edged past Swansea at the Liberty Stadium thanks to a first-half goal from Lee Williamson.
Williamson scored when Watford lost 3-1 at Swansea three days ago and hit the back of the net again after 21 minutes when he turned and lashed a shot past Dimitrios Konstantopoulos in the Swansea goal.