Arsenal scored three goals in eight second-half minutes to thrash rock-bottom Sunderland 4-1 and keep pace at the top of the Premier League.
Alexis Sanchez put the Gunners ahead in the 19th minute but Sunderland responded in the second-half thanks to Jermain Defoe's penalty after Duncan Watmore was brought down by Petr Cech.
With the game in the balance Arsene Wenger introduced Olivier Giroud and the Frenchman scored with his first touch in the 71st minute before securing the points with a deft header five minutes later.
Sanchez completed the scoring in the 78th minute, his 50th Arsenal goal helping the Gunners stay level with Manchester City at the summit, while piling more pressure on Sunderland boss David Moyes.
Defeat leaves the hosts with just two points after 10 games, their -13 goal difference meaning this is the worst start to a Premier League season.
Arsenal were forced into two changes at the Stadium of Light with both Theo Walcott and Nacho Monreal failing late fitness tests. Alex Oxlade-Chamberlain and Kieran Gibbs came into the side and were both heavily involved as Arsenal dominated the early stages.
In just the second minute Sunderland goalkeeper Jordan Pickford's nervy clearance was closed down by Sanchez before the goalkeeper was forced to turn behind an Oxlade-Chamberlain's header just a few moments later.
Sunderland were struggling to have any impact on the game, unlike Sanchez, who was involved in almost everything for the visitors. The Chile international's inch-perfect through ball picked out the run of Mesut Ozil in the 13th minute but the German's shot was easily saved.
A minute later and Arsenal were in again after Sanchez's pass released Francis Coquelin, but the Frenchman didn't have the pace to get away from Lamine Kone.
The breakthrough eventually came for the Gunners in the 19th minute as Oxlade-Chamberlain burst past Duncan Watmore before producing a brilliant cross for Sanhcez, who nipped in ahead of Kone, to head his side in front.
Five minutes later, Sunderland though they were back on level terms as Defoe swept home from close range, however, Wahbi Khazri was rightly ruled to be offside in the build-up.
Oxlade-Chamberlain, who scored twice in midweek in Arsenal's EFL Cup win against Reading, threatened again as the first-half came to a close but his low effort was comfortably saved by Pickford,
The England international was involved again minutes later as his pass released Ozil, who should have made it 2-0 but did not get enough on his lobbed attempt to let the advancing Pickford and his team-mates off the hook.
Sunderland returned after the break in a more determined mood, but Oxlade-Chamberlain squandered another golden opportunity after being played in behind a square defence once again and Sanchez was astonished not to be awarded a 62nd-minute penalty after going down under Kone's challenge.
Referee Martin Atkinson, however, did point to the spot at the other end two minutes later after Watmore had skipped away from the Arsenal defence and been tripped by Cech, and Defoe obliged from 12 yards to level the scores.
But the joy was short-lived for the home fans as Giroud scored with his first two touches after coming on as a substitute, sweeping home Gibbs' cross to restore his side's lead and heading home Ozil's cross five minutes later.
Sanchez converted from close range moments later after Gibbs' powerful shot rebounded off the post to complete a miserable afternoon for Sunderland and leave them rooted to the bottom of the table.
Sunderland: Pickford (6), Jones (6), Kone (5), O'Shea (5), Van Aanholt (6), Watmore (6), Rodwell (5), Ndong (5), Pienaar (6), Khazri (5), Defoe (6).
Subs used: Djilobodji (5), Januzaj (5), Gooch (N/A).
Arsenal: Cech (6), Bellerin (7), Mustafi (7), Koscielny (7), Gibbs (8), Elneny (7), Coquelin (7), Oxlade-Chamberlain (7), Ozil (7), Iwobi (7), Sanchez (9).
Subs used: Ramsey (6), Giroud (8), Maitland-Niles (N/A).
Man of the match: Alexis Sanchez.