Match ends, Arsenal 1, Southampton 0.
- Arsenal in sixth position in league
- Southampton three points above Gunners in third
- Saints have never won at Arsenal in Premier League
- Visitors had one shot on target
Alexis Sanchez struck two minutes from time to give Arsenal victory just as it looked like Southampton would hold out for a draw at The Emirates.
Visiting goalkeeper Fraser Forster had kept Arsenal at bay with a collection of fine saves from Danny Welbeck and substitute Olivier Giroud, but he was powerless to prevent Gunners talisman Sanchez pouncing on Aaron Ramsey's cross to score his 14th goal of the season.
Arsene Wenger's side deserved the win after applying intense late pressure but Southampton were forced to play out the crucial final minutes without defender Toby Alderweireld, who suffered a hamstring injury after manager Ronald Koeman had used his three substitutes.
The victory, coming on the heels of the win at West Bromwich Albion on Saturday, pushes Arsenal into the top six, while Saints stay third despite a second successive defeat following their home loss against Premier League champions Manchester City on Sunday.
A small group of Arsenal fans brandished a banner at The Hawthorns calling for Wenger to quit, but they can be grateful that he has brought such a gem as the Chilean Sanchez to north London.
Just as the frustration of potential dropped points was building at The Emirates, the former Barcelona forward succeeded where other Arsenal strikers had failed to secure an important win.
Welbeck had the first opportunity of the night when he was played in by Santi Cazorla's pass but he could not get himself set and ended up steering a presentable chance just wide.
|Alexis Sanchez has scored nine goals after 14 league matches for the first time in European football||It is the first time in nine league games Aaron Ramsey has been involved in a goal for Arsenal|
|Mathieu Flamini completed 64 of his 69 passes for the Gunners||Southampton goalkeeper Fraser Forster made seven saves compared to Emiliano Martinez's one|
Saints had gathered in plenty of confidence during an excellent start to the season and they opened with plenty of ambition. Graziano Pelle should have put them ahead in the 15th minute but he shot wildly over.
Neither goalkeeper saw serious action until first-half stoppage time, when Southampton's Forster reacted well to turn Welbeck's flicked header over the top. The striker also tried a backheel at the near post but was crowded out by Saints' defenders.
As anxiety grew inside The Emirates, Wenger made the change demanded by Arsenal's fans when he introduced Giroud, although the decision to take off Alex Oxlade-Chamberlain was met with some jeers.
Giroud almost immediately tested Forster with a snap shot as Arsenal attempted to finally apply concerted pressure on a resolute and well-organised Southampton defence.
The French striker then showed initiative with a neat flick to release Welbeck but Forster's reactions again came to the Saints' rescue as he made a fine one-handed save.
It seemed the England goalkeeper was going to keep Arsenal at bay when he showed great athleticism to claw away Giroud's header but, just when it looked like Saints would survive despite their numerical disadvantage, Sanchez made the breakthrough.
Southampton manager Ronald Koeman: "We had a good positive reaction after last Sunday - a good first half, good ball possession, a good chance off Pelle. After an hour it was more difficult, Arsenal were pressing more but the difference was 11 v 10.
"We were unlucky to get a player injured after making all of our substitutions, you know they will create chances and in the last few minutes they made it 1-0."
- 15Oxlade-ChamberlainSubstituted forGiroudat 65'minutes
- 23WelbeckSubstituted forPodolskiat 81'minutes
- 6José Fonte
- 17AlderweireldBooked at 43mins
- 12WanyamaBooked at 76mins
- 18CorkSubstituted forYoshidaat 29'minutes
- 7LongSubstituted forMayukaat 81'minutes
- 11TadicSubstituted forManéat 62'minutes
- Andre Marriner
- Shots on Target
Second Half ends, Arsenal 1, Southampton 0.
Alexis Sánchez (Arsenal) wins a free kick on the right wing.
Foul by Sadio Mané (Southampton).
Corner, Arsenal. Conceded by Maya Yoshida.
Attempt missed. Lukas Podolski (Arsenal) left footed shot from the left side of the box misses to the right. Assisted by Alexis Sánchez.
Corner, Arsenal. Conceded by Fraser Forster.
Attempt saved. Aaron Ramsey (Arsenal) left footed shot from the centre of the box is saved in the bottom left corner. Assisted by Olivier Giroud with a through ball.
Goal! Arsenal 1, Southampton 0. Alexis Sánchez (Arsenal) right footed shot from the centre of the box to the bottom left corner. Assisted by Aaron Ramsey.
Attempt saved. Olivier Giroud (Arsenal) header from the centre of the box is saved in the bottom left corner. Assisted by Lukas Podolski with a cross.
Aaron Ramsey (Arsenal) wins a free kick in the defensive half.
Foul by Victor Wanyama (Southampton).
Foul by Alexis Sánchez (Arsenal).
Sadio Mané (Southampton) wins a free kick in the defensive half.
Toby Alderweireld went off injured after Southampton had used all subs.
Attempt saved. Lukas Podolski (Arsenal) left footed shot from outside the box is saved in the centre of the goal. Assisted by Olivier Giroud.
Delay over. They are ready to continue.
Delay in match Toby Alderweireld (Southampton) because of an injury.
Alexis Sánchez (Arsenal) wins a free kick in the defensive half.
Foul by Ryan Bertrand (Southampton).