Arsenal manager Arsene Wenger says his side have done "half a job" after a "spectacular" first-half performance saw the Gunners take control of their Europa League quarter-final by demolishing CSKA Moscow in the first leg.

Alexandre Lacazette and Aaron Ramsey scored two goals each as the Gunners hit four in 26 minutes before half-time.

Arsenal were unable to add to their tally in the second half but they will head to Russia's capital for the second leg next Thursday with a commanding lead.

"We have to be realistic. We have to do the job over there, go and try to win the game, that's the best way," said Wenger.

Ramsey's side-foot finish set Arsenal on their way.

Aleksandr Golovin levelled with a sublime free-kick before France striker Lacazette, who has recovered from a knee injury, made it 2-1 with a penalty after Mesut Ozil was fouled by Georgi Schennikov.

Ramsey produced a brilliant third with an instinctive volleyed flick, with Lacazette adding a fourth after being picked out by the outstanding Ozil.

"We have done half of a job," added Wenger. "There was a good pace in the first half, the two teams gave everything, which is why is was such a spectacular first half."

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Gunners warming to Europa League

Arsenal, who have now won five straight games, should have triumphed by a more handsome margin in what was a cracking match.

Mkhitaryan missed a great chance early in the second half, while Ramsey fired over the bar after keeper Igor Akinfeev had spilled the ball into his path.

Ramsey's hopes of a hat-trick disappeared when his curling 77th-minute shot hit the post.

Nevertheless, Wenger's side will be confident of reaching the semi-finals of a competition that provides a team sixth in the Premier League - 13 points off fourth place with seven games left - with their most realistic chance of qualifying for next season's Champions League.

Arsenal are certainly warming to the Europa League, collecting their eighth win from 11 games in the competition, scoring 27 times and conceding eight.

Assuming there is no second-leg upset in Russia, they still need to negotiate a two-legged semi-final to reach the final in Lyon on 16 May.

Yet the way they dismantled CSKA, who started their European campaign in the Champions League, was impressive - although victory came at a cost.

Wenger confirmed after the game that keeper David Ospina, who suffered an ankle injury on the eve of the game, will be out for between two and three weeks, while Mkhitaryan, who was substituted, will miss Sunday's game against Southampton with a damaged knee.

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Ramsey's special finish

There have been some spectacular goals in Europe this week.

Cristiano Ronaldo's superb overhead kick for Real Madrid against Juventus in the Champions League was followed by Alex Oxlade-Chamberlain's rocket shot for Liverpool against Manchester City.

Ramsey's second goal was also sumptuous.

The Gunners were leading 2-1 when the Wales midfielder, spotting Akinfeev off his line, lifted the ball over the CSKA keeper from Ozil's wonderful pass.

It was an audacious first-time finish and it left CSKA deflated as the Russian side conceded four goals in the space of 26 minutes.

"When Ramsey plays game after game he's not only involved in the build-up, he's now calmer in his finishing," added Wenger.

Ramsey had scored the first of Arsenal's four first-half goals with a finish high into the net and the midfielder, who scored against AC Milan in the last round at the San Siro, now has nine for the season.

He also had a goal ruled out for offside while the game was goalless before Arsenal went on to deliver a masterclass in attacking football.

Man of the match - Mesut Ozil (Arsenal)

Best first-half European goal blitz for 14 years - the stats

• This was the first time Arsenal scored four goals in the first half of a European game since December 2004 against Rosenberg in the Champions League group stage.
• The Gunners have won five matches in a row in all competitions for the first time since a run of six victories ending in May 2017.
• Arsene Wenger's side have won three consecutive knockout games in European competitions for the first time since 1999-2000, when they won four successive matches in the Uefa Cup quarter-finals and semi-finals.
• CSKA Moscow have now lost four successive European matches on English soil, shipping 10 goals in the process.
• Alexandre Lacazette has scored 10 goals in his last 13 Europa League appearances, these being his first two for Arsenal in the competition (after scoring eight for Lyon).

What's next?

Arsenal are back at Emirates Stadium on Sunday when they host Southampton (14:15 BST), while CSKA Moscow host rivals Dynamo Moscow in a derby on Monday (17:30 BST), before next Thursday's second leg in the Russian capital.