Arsenal 1-2 Ostersunds FK (4-2 agg)

Sead Kolasinac's fourth goal for Arsenal quelled Ostersund's comeback

Arsenal boss Arsene Wenger said his side were complacent as they survived a huge scare against Swedish minnows Ostersunds FK to claim a place in the last 16 of the Europa League.

The Gunners won the first leg 3-0 but one of football's great shocks looked possible at half-time after the visitors struck two goals in 70 seconds.

Graham Potter's side, who have risen from Sweden's fourth tier since 2010, were on top in the first half and led 2-0 thanks to Calum Chambers' own goal - deflecting in Hosam Aiesh's shot - and Ken Sema's clinical strike.

But the Gunners - who named a reasonably strong side only three days before their Carabao Cup final with Manchester City - improved slightly after the break and Sead Kolasinac finished from Hector Bellerin's cross to relieve the sense of dread inside Emirates Stadium.

"We were not at the races in the first half," said Wenger, who saw his side booed off at half-time and full-time.

"I think in the second half it was much better and we should have scored a few goals.

"In the first half we were in trouble and in danger because we were complacent, not focused and were open every time we lost the ball. We had no ideas with the ball and that's why we were in trouble.

"We responded very well because we did the job to qualify, but that's what we have to take from the night and that's all."

Arsenal, who have never won the Uefa Cup or Europa League, will discover their last-16 opponents at 12:00 GMT on Friday.

Ostersund are only the second team to win a game at the Emirates in the Gunners' last 28 matches - a run dating back to March 2017.

• Relive Osterund's famous win at the Emirates

'Not a formality' said Wenger - he wasn't wrong

This is Arsenal's first season in the Uefa Cup/Europa League since they lost the 2000 final to Galatasaray

Wenger made only three changes from the first leg and the Frenchman insisted the game was "not a formality".

But even with 21 years' experience at the club, surely even he did not foresee what was to come in the first half, with the hosts looking shell-shocked and Ostersund fully deserving of the lead.

Chambers was arguably at fault for both strikes. For the first, he turned home Aiesh's shot and for the second he was beaten to the ball by Sema and then turned away from the winger's superb finish.

Things got better in the second half, although had they got worse this would probably have gone down as Wenger's lowest point as Arsenal boss.

Granit Xhaka replaced young midfielder Ainsley Maitland-Niles at the break and the Gunners looked reasonably comfortable once Kolasinac took advantage of Ronald Mukiibi's air-kick from Bellerin's cross to lash home.

Danny Welbeck had four chances to score, but he headed two straight at Aly Keita, chipped the other to the goalkeeper and shot straight at him again in the last minute.

Welbeck's efforts typified a poor night for the hosts, and on this evidence these players will not have given Wenger any selection problems for Sunday's EFL Cup final at Wembley.

"We prepared properly and in a serious way," said Wenger. "But you have external circumstances such as the fact we won 3-0, the fact that we have another big game on Sunday, the fact that people subconsciously think you just have to turn up to win the game. Football doesn't work like that.

"It's better not to talk too much tonight, and focus on our next game."

Ostersund's fairytale comes to an end (for now)

Arsenal were on the ropes when Ken Sema scored Ostersund's second

Ostersund might be out - but a 14-game debut European campaign ending in a victory at Arsenal is a story for the ages.

For a team who have not played a league game since November - the Swedish league is a summer event - they showed no sign of rustiness.

Their remarkable story has been told many times this season: since Englishman Potter's appointment in 2010, they have risen from the fourth tier to win last season's Swedish Cup and qualify for Europe.

Potter said before the game they needed a "miracle" and after 23 minutes, it looked like a genuine possibility.

Jamie Hopcutt, whose last English club was Tadcaster Albion, had an early shot blocked and Sema forced a save from David Ospina at his near post.

Their fans were still celebrating the opening goal, perhaps slightly harshly taken away from Aiesh and deemed an own goal, when Sema smashed home their second. Saman Ghoddos - praised by Wenger after the first leg - helped set up both goals.

Curtis Edwards, another former English non-league player, shot wide from 30 yards and Ghoddos had a free-kick saved by Ospina as they pushed for an aggregate equaliser.

The dream was practically over after Kolasinac's strike but their heads did not drop - they kept going and they still had chances to score again.

They finished fifth in the 2017 Swedish league, not good enough for European qualification, but they can still return if they win the Swedish Cup, which runs from the summer until the spring.

Potter also joins a select club as only the sixth English manager to win a game at the Emirates, along with Alan Curbishley, Phil Brown, Harry Redknapp, Michael Appleton and Garry Monk.

Man of the match - everyone at Ostersund

Ostersund's entire squad and manager Graham Potter deserve so much praise for a season in which they knocked out five teams, including Galatasaray and Hertha Berlin, before running Arsenal close

'Just short of the miracle'

Ostersunds FK boss Graham Potter, speaking to BT Sport: "I am very, very proud of the players and the supporters. To play in the manner we did I felt we showed real courage and bravery and played some good football against a top team.

"At 2-0 we thought we had a chance. We played well, won the game but it was just short of the miracle.

"Apart from the first 20 minutes at home we went toe-to-toe with Arsenal which is no mean feat considering where we have come from.

"It is a learning experience we have been having. It was the first time we were playing in the last 32. Over the course of the game we have shown what we are about and what we are trying to do. Today is a day to be proud of what we did over the two matches."

Stats - 33% of Arsenal own goals are from Chambers

• Despite progressing into the next round, Arsenal have now lost each of their last six home games in the knockout rounds of European competition.

• Arsenal's defenders have contributed 20 goals in all competitions this season, the most of any Premier League side (Chelsea 16, Man City 10).

• The Gunners have conceded in each of their last six at the Emirates in all competitions; their longest run without a clean sheet there since May 2014 (seven consecutive games).

• Ostersunds FK are the first Swedish side to win an away European match in England since Osters IF beat Tottenham Hotspur in the 1995 Intertoto Cup.

• Arsenal have scored nine own goals since Calum Chambers debuted for them in August 2014 - he has been responsible for 33% of them (three).

What's next?

Arsenal play Manchester City twice in the next eight days. The EFL Cup final is followed by Thursday's Premier League game at Emirates Stadium.

Ostersund's league season does not start until April. But they are in Swedish Cup group stage action on Monday, away to third-tier Atvidaberg.