* Arsenal win London derby 2-0 to reach fourth round
* Villa knocked out by lower league Sheffield United
* Everton, Southampton, Stoke and Palace all progress
* Cardiff win at Newcastle under new boss Solskjaer
* Holders Wigan, losing finalists Man City both draw (Adds details, quotes)
By Tim Collings
LONDON, Jan 4 (Reuters) - Premier League leaders Arsenal showed their class as they comfortably beat north London rivals Tottenham Hotspur 2-0 to book a place in the FA Cup fourth round in an electric atmosphere at the Emirates Stadium on Saturday.
Goals from forward Santi Cazorla and midfielder Tomas Rosicky, after 31 and 62 minutes respectively, sealed a smooth passage for the 10-times winners after an open contest in which the visitors played their part in a stirring contest.
Arsenal joined fellow top-tier sides Everton, Southampton, Stoke City, Crystal Palace, who won 2-0 at West Bromwich Albion, and Cardiff City, 2-1 victors at Newcastle United in their first outing under new manager Ole Gunnar Solskjaer, in progressing.
But seven-times winners Aston Villa crashed 2-1 at home to third tier Sheffield United in their third round tie.
Cup holders Wigan Athletic, relegated from the top flight last term, were held to a 3-3 draw by League One (third tier) MK Dons, while losing finalists and league title favourites Manchester City drew 1-1 at second tier Blackburn Rovers.
Arsenal, missing several first-choice players, took control against Spurs with some typically fast-flowing attacking play before Spaniard Cazorla scored his first FA Cup goal.
Arsenal's French right back Bacary Sagna initiated the move with a surging run and pass inside to 18-year-old German winger Serge Gnabry who, after a run that drew three defenders, set up Cazorla for a thunderous left-foot drive from 20 metres.
Tottenham, urged on by their pocket of fans in a noisy crowd, rallied but their response stalled when Rosicky caught left back Danny Rose in possession and ran clear before scooping the ball over advancing French goalkeeper Hugo Lloris.
It was the Czech's first goal of the season.
"I always try to put the opponent under pressure and it paid off - my first goal and against our main rivals, so it feels very good," said Rosicky.
"I think we played collectively and we played very well. It was important not to make mistakes and we know that always we have the quality to score goals."
Arsenal might have added a third after 77 minutes, but England winger Theo Walcott shot wide from 15 metres before suffering a knee injury. He was carried off and the Gunners comfortably played out the final minutes with 10 men.
"I thought we played well in defence and in attack and controlled the game which was played at quite a pace," Arsenal manager Arsene Wenger told reporters. "Our game was based on quick, sharp passing and we were dangerous."
Earlier, on an afternoon of few major surprises, League One (third tier) Sheffield United knocked out Villa, whose manager Paul Lambert had said beforehand that the FA Cup was little more than "a distraction" for most Premier League clubs.
League Two (fourth tier) Rochdale similarly made light of the 45 places separating them from Championship side and 1972 FA Cup winners Leeds United by beating them 2-0 to reach the fourth round for the first time since 2003.
Villa's defeat, courtesy of a fine goal in each half from Jamie Murphy and Ryan Flynn, who scored with a magnificent 25-metre shot before substitute Nicklas Helenius responded, heaped more pressure on under-fire manager Lambert.
After trudging up the tunnel at Villa Park with the wrath of the home supporters ringing in his ears, he conceded: "I don't think we did enough to go through and that is me being honest.
"We had a lot of the ball and huffed and puffed. It was one of those kind of games..."
United, 51 places below Villa in the English league pyramid, reached the fourth round for the sixth time in seven seasons.
"The players were incredible today," manager Nigel Clough told reporters. "You can fluke a result in a cup, but I thought we deserved that win. We played some magnificent stuff at the start of the second half.
"We like to be positive and the lads like to enjoy it, as they did, while working incredibly hard. We've had a rough six months so this puts a smile on people's faces."
Rochdale also had plenty to enjoy after their pulsating display against Leeds.
Manager Keith Hill said: "It's a tremendous win. We had a gameplan and the players executed it superbly. They trusted me and each other. No-one can argue we didn't deserve that win."
Leeds boss Brian McDermott told the BBC: "I would probably say that is my worst moment in football."
There are six more ties on Sunday including Chelsea's visit to Championship side Derby County, Manchester United at home to Swansea City and Liverpool against third tier Oldham Athletic. (Reporting by Tim Collings, editing by Martyn Herman and Ken Ferris)