London - Olivier Giroud made amends for a first-half own goal as Arsenal beat struggling Sunderland 3-1 on Saturday to move up to second place in the Premier League table.
The London club took advantage of Manchester City's 2-0 defeat at Stoke City and Manchester United's failure to beat West Ham United by registering their first win in four league games.
It was a timely boost ahead of next week's must-win Champions League trip to Olympiakos, where Arsene Wenger's side must prevail by two clear goals to reach the knockout phase.
Joel Campbell put the Gunners ahead in the 33rd minute and Giroud restored their lead mid-way through the second half after he had gifted the visitors an equaliser on the stroke of half-time, with Aaron Ramsey wrapping up the win in added time.
The victory helped to draw a line under another testing week for Wenger after the loss of Alexis Sanchez and Santi Cazorla to injury following last weekend's 1-1 draw at Norwich City.
Cazorla is expected to be out for at least three months after damaging knee ligaments, while no return date has yet been set for the return of Sanchez, who pulled a hamstring at Carrow Road.
Wenger could at least call on fit-again centre-back Laurent Koscielny, while Theo Walcott was back in the squad for the first time since late October after recovering from a calf problem.
Sunderland arrived at the Emirates Stadium on the back of successive victories - they had won just one their opening 12 league games - that had lifted them out of the relegation places.
Their growing confidence was immediately apparent as Fabio Borini was sent clear in the fourth minute and wasted a good opportunity by shooting straight at Arsenal goalkeeper Petr Cech.
Arsenal's back four looked distinctly shaky during the opening stages, while up front the home side were also lacking in fluency, but when they did click, it culminated in the opening goal.
Ramsey, moved back into his preferred central role in place of Cazorla, played the ball into the feet of Giroud, who laid the ball back to Mesut Ozil.
The German playmaker threaded an excellently weighted pass inside right-back DeAndre Yedlin, allowing Campbell to run onto the ball and steer a first-time shot past Costel Pantilimon.
The quality of the move suggested Arsenal had finally found their rhythm, but the defensive frailties returned when Giroud diverted the ball into his own net as he attempted to clear Yann M'Vila's in-swinging free-kick.
Sunderland deserved to be level at the break and could have gone ahead early in the second half when Steven Fletcher tested Cech twice in the space of barely a minute.
The Scotland striker saw a low drive turned around the post and from the resulting corner he raced in at the back post to meet Ola Toivoinen's flick-on, only for Cech to brilliantly claw his shot off the line.
But Arsenal responded well, improving as the game progressed and re-establishing their lead in the 63rd minute when Giroud produced an excellent diving header from Ramsey's cross.
Ramsey completed the win in injury time when he poked the ball past Pantilimon after good work by Walcott.