A tactical switch by Arsene Wenger has made free-scoring Arsenal look like title contenders before Saturday's Premier League trip to champions Manchester United.
Chelsea's 0-0 home draw with second-placed United ensured Thomas Tuchel is still undefeated in nine games since replacing Frank Lampard, but it meant they failed to dislodge fourth-placed West Ham United who became Manchester City's 20th successive victims in all competitions on Saturday.
Arsenal will tackle arch-rivals Manchester United in their search for a 50th successive Premier League match without defeat.
Chelsea moved to within three points of Manchester United in the Premier League after a 0-0 draw with Liverpool and United were upset by Manchester City.
The Gunners will take on Manchester United at Old Trafford in the FA Cup fifth round.
Images from Sunday's action in the Premier League.
Arsenal beat Sunderland 3-2 on Sunday to move back to the top of the Premier League after Robin van Persie secured victory with a well-worked winner 10 minutes from time.
Manchester United, winners of the competition in 2017, will have a lot of travelling to do to Eastern Europe after being drawn alongside Kazakhstan side Astana, Serbia's Partizan Belgrade and Dutch side AZ Alkmaar.
Arsenal and Liverpool drew 1-1 for the third time this season on Saturday as the London side's Premier League title hopes suffered another blow. Arsenal could now end the weekend eight points behind league leaders Manchester United with five games left.
Liverpool roared back from a goal behind to thrash Tottenham Hotspur 5-1 and wrap up the English Premier League title in style.
In the other pairings, English champions Manchester United will take on Greek club Olympiakos, while AC Milan take on Atletico Madrid.
Arsenal produced a scintillating display of attacking football to crush Crystal Palace 5-1.
Ronaldo's 62nd minute strike was his 17th league goal this season
Striker Robin van Persie has recovered from a groin strain and returns to Arsenal's squad for the Champions League semi-final second leg against holders Manchester United on Tuesday, manager Arsene Wenger said.
Cesc Fabregas scored twice to send Arsenal second in the Premier League, four points behind Chelsea but with a game in hand, after brushing aside Aston Villa 3-0 at the Emirates Stadium on Sunday.
Manager Roy Hodgson has hinted that Liverpool are unlikely to mount a Premier League title challenge this season.
Reading enjoyed a memorable first taste of the top flight when they beat Middlesbrough 3-2.
Arsenal went top of the Premier League when they beat West Ham United 2-0 with goals from Denilson and Cesc Fabregas on Saturday despite playing for more than half the match at the Emirates with 10 men.
Yuvraj Singh said he has been following Manchester United for more than 20 years
Bethany England's early rocket proved enough for Chelsea as they beat newcomers Tottenham Hotspur 1-0.
Stunning hat-tricks from Dimitar Berbatov and Robin van Persie moved Manchester United and Arsenal ahead in the Premier League title race as strikers took the spotlight on Saturday.
Mason Greenwood's late winner earned Manchester United a 1-0 win at wasteful Wolverhampton Wanderers in the Premier League on Sunday, breaking the record for the longest unbeaten away run in English Football League history in the process.
A round-up of the weekend's action in the major European leagues.
Arsenal are buzzing after their resounding victory over north London rivals Tottenham Hotspur but they go into Wednesday's Champions League home clash with Montpellier aware that any slip could be costly to their last 16 hopes.
The teams clash at the Etihad stadium on Sunday (1700 IST) with United three points clear of champions City.
Manchester United needed a stoppage-time equaliser to draw 1-1 with 10-man Blackburn Rovers in the English Premiership.
Manchester United were celebrating their eighth premier league title in 11 seasons on Sunday after Arsenal lost 3-2 at home to Leeds.
Manchester United needed a stunning second-half equaliser from Wayne Rooney and a rare goal from Wes Brown to beat Newcastle United 2-1.
Manchester United stretched their unbeaten run to 11 games in all competitions after Daley Blind, in-form striker Zlatan Ibrahimovic and substitute Henrik Mkhitaryan gave them a 3-1 home win over Sunderland on Monday. Left back Blind fired United ahead with a crisp 39th-minute shot after Ibrahimovic teed him up perfectly. The towering Swede doubled the lead with a clinical 82nd-minute finish for his 17th goal of the season. Fit-again Mkhitaryan put the icing on the cake with a spectacular backheel effort after a sharp Ibrahimovic cross from the right, although television replays suggested the Armenian was marginally offside. Striker Fabio Borini gave Sunderland fans something to cheer with a dipping late volley.
Manchester United beat Liverpool 2-1 with goals from Wayne Rooney and Park Ji-sung to send the champions back to the top of the Premier League on Sunday.
Arsenal's Olivier Giroud produced a piece of New Year's Day magic to keep Arsenal in sight of Premier League leaders Chelsea while Harry Kane's double bolstered Tottenham Hotspur's ambitions as London's triple assault on the title continues.
Arsenal beat north London rivals Tottenham Hotspur 3-1 to surge top of the English Premier League.
