Match ends, Arsenal 3, Southampton 2.
Arsenal manager Arsene Wenger praised the "exceptional" mental strength of Danny Welbeck after the striker ended a goalless run of 16 Premier League games to score two and assist the other as the Gunners fought back to beat Southampton.
Wenger had made seven changes with Thursday's Europa League quarter-final second leg against CSKA Moscow in mind, and his side trailed when Shane Long capitalised on a first-half mix-up between keeper Petr Cech and centre-back Shkodran Mustafi.
But the hosts recovered with Pierre-Emerick Aubameyang prodding in his sixth goal since joining from Borussia Dortmund for £56m in January to level before Welbeck - who created the equaliser with a clever flick - put them ahead.
Southampton then drew level when substitute Charlie Austin turned in Cedric Soares' cross but Welbeck headed Arsenal back in front after both sides missed a string of chances, leaving the visitors deep in relegation trouble.
"It's not easy because we played against a team who fights not to go down, mentally it is very difficult," Wenger said.
"Some of our players had heavy legs but we still won the game when we were questioned, I really like the spirit in this team.
"Every game you win makes you stronger, it's important that you keep your run going. We have gone through a difficult spell, but because the players are proud we came back. Now we hope to keep this going."
He singled out Welbeck's contribution in the game at Emirates Stadium after the 27-year-old scored for the first time in the league since September, then got the winner after shooting high over the bar from close range four minutes earlier.
"I think I have repeated that I really like Danny Welbeck," Wenger said.
"I am very pleased for him because he is a guy who went through a very difficult time and has shown exceptional mental strength to come back."
Mark Hughes' men, who had defender Jack Stephens sent off in added time before Arsenal's Mohamed Elneny was also dismissed, remain 18th in the table and three points from safety.
The south-coast outfit also had a second Long goal ruled out for offside and defender Wesley Hoedt saw his header cleared off the line by Elneny.
Goalkeeper Alex McCarthy had kept the visitors' second-half hopes alive with a string of impressive stops to deny Aubameyang, Granit Xhaka and Alex Iwobi.
Late drama lifts Emirates inertia
A sterile first-half atmosphere at the Emirates, after a similarly muted last league win against Stoke, was transformed by a dramatic second half in north London.
Arsenal won over their supporters with a display of grit to keep their winning momentum going as the focus shifts to Europe again.
It is now six consecutive triumphs in all competitions and they sit sixth in the Premier League table.
And this 150th win at their home ground since they left Highbury in 2006, adds more weight to Wenger's claim that their relative woes this term maybe require a little perspective.
They seem almost certain to miss out on the top four again this season after that happened last term for the first time in 20 years.
But even without the influential Mesut Ozil and Jack Wilshere in their starting line-up they had the mental strength to take all three points against determined opposition.
"If you look at our home season, people have seen good football here and I read somewhere that we were the third best team in the league with our home results," Wenger said last week.
After leading twice, two late red cards and and a surprisingly loud roar at the final whistle, there was certainly entertainment at the Emirates on Sunday despite the empty seats.
Wenger and his players head to Moscow with a spring in their step, still believing they can reach the Champions League next season by winning the Europa League. They hold a 4-1 advantage from the first leg of the quarter-final.
Saints show better attacking instinct
Statistics do not always tell the full story, especially in a game when Southampton gave so much, but the numbers are stacking up against them with time running out.
It is just one win in 19 league matches now and they have conceded six goals in two league games since Hughes replaced the sacked Mauricio Pellegrino in the middle of March.
The hard luck tales kept coming on Sunday. James Ward-Prowse had a goalbound shot cleared off the line by Hector Bellerin, Hoedt too went close and Welbeck's first Arsenal goal took a deflection off Maya Yoshida.
But if they keep alive the battling spirit they displayed against Arsenal, they might still make it to safety.
Ward-Prowse, making his 200th appearance for the club aged just 23, ran further and made more sprints than anyone else on the pitch, and Long constantly stretched Arsenal with darts behind their defence.
It does not get any easier for them, though, with fifth-placed Chelsea up next before a trip to Leicester, who are eighth.
But while they were toothless in attack during their previous 3-0 defeat at West Ham, this time they had more shots on target than their expensively assembled hosts.
The question is whether Hughes has enough time left to implement his ideas.
Saints have six Premier League games remaining, as well as an FA Cup semi-final, and there were signs here they are finding some resilience.
Gunners shine at home - the stats
- Arsenal have won six matches in a row in all competitions for the first time since May 2017 (also six).
- The Gunners have scored three or more goals in five successive home games in all competitions for the first time since their opening six matches of the 1958-59 season.
- Southampton have lost three successive away league matches conceding at least three goals in each for the first time since September 2013, under Nigel Adkins (a run of four).
- Southampton have not won any of their last six Premier League games in which they have opened the scoring (drawn four, lost two).
- Danny Welbeck both scored and assisted in a Premier League match for the first time since September (against Bournemouth), which was also the last time he netted a league goal.
- Pierre-Emerick Aubameyang has been directly involved in seven goals in his first seven Premier League games (six goals, one assist), more than any other player in their first seven appearances for the Gunners.
- Shane Long has scored four goals against Arsenal in the Premier League, only against Aston Villa (six) has the Irishman netted more often.
- In fact, only Wayne Rooney (seven) and Robin van Persie (six) have scored more Premier League goals against Petr Cech than Shane Long (five).
- Charlie Austin has scored in each of his four Premier League games against Arsenal (four goals), including in both of his appearances at the Emirates.
'Wilshere could have been sent off too' - what they said
Southampton boss Mark Hughes, speaking to Sky Sports: "We have difficult games coming up, we know that but we have to show qualities and strength in our mindset. Our confidence has been a bit low but it won't be damaged by today, it will be enhanced."
On Jack Stephens' red card: "I've got to be careful, it's not an easy role clearly but Jack reacted to Wilshere pulling him back, he was reacting to get rid of him, and I'm a bit disappointed that the ref didn't see what I thought was a movement with his knee - he could have been sent off as well."
Man of the match - Danny Welbeck (Arsenal)
Arsenal travel to CSKA Moscow on Thursday for the second leg of their Europa League quarter-final (20:05 BST), while Southampton host Chelsea on Saturday (12:30 BST).
- 24BellerínBooked at 50minsSubstituted forHoldingat 74'minutes
- 35ElnenyBooked at 90mins
- 61NelsonSubstituted forWilshereat 64'minutesBooked at 90mins
- 14AubameyangSubstituted forLacazetteat 71'minutes
- 5StephensBooked at 90mins
- 3YoshidaSubstituted forAustinat 72'minutes
- 6HoedtBooked at 90mins
- 2Cédric Soares
- 7LongSubstituted forSimsat 80'minutes
- Andre Marriner
- Shots on Target
Second Half ends, Arsenal 3, Southampton 2.
Wesley Hoedt (Southampton) is shown the yellow card for a bad foul.
Alexandre Lacazette (Arsenal) wins a free kick on the right wing.
Foul by Wesley Hoedt (Southampton).
Mohamed Elneny (Arsenal) is shown the red card for violent conduct.
Jack Wilshere (Arsenal) is shown the yellow card.
Jack Stephens (Southampton) is shown the red card for violent conduct.
Foul by Jack Wilshere (Arsenal).
Jack Stephens (Southampton) wins a free kick on the right wing.
Attempt blocked. Pierre-Emile Højbjerg (Southampton) right footed shot from the centre of the box is blocked.
Foul by Danny Welbeck (Arsenal).
Oriol Romeu (Southampton) wins a free kick in the defensive half.
Sead Kolasinac (Arsenal) wins a free kick in the defensive half.
Foul by Charlie Austin (Southampton).
Attempt blocked. Josh Sims (Southampton) right footed shot from the right side of the box is blocked. Assisted by Charlie Austin.
Corner, Southampton. Conceded by Petr Cech.
Attempt saved. Dusan Tadic (Southampton) left footed shot from the left side of the box is saved in the top left corner. Assisted by Ryan Bertrand with a headed pass.
Alex Iwobi (Arsenal) wins a free kick in the defensive half.
Foul by Ryan Bertrand (Southampton).