An Aaron Ramsey strike and a Kalidou Koulibaly own goal gave Arsenal a 2-0 victory over Napoli in the first leg of their Europa League quarter-final on Thursday - and a rare and valuable clean sheet to take to Italy in a week's time.
Arsenal took the lead in the 14th minute through Ramsey, who finished off a sweeping move down the right by calmly slotting the ball past Napoli goalkeeper Alex Meret.
They doubled the advantage 10 minutes later after a moment of individual brilliance from Lucas Torreira, who dashed through the Napoli midfield before spinning and switching the ball to his left foot and letting fly.
The Uruguayan's shot took a heavy deflection off Senegal defender Koulibaly and was registered as an own-goal.
"We can be happy with this result, but (Napoli) are going to be more competitive away. Our challenge - our success - is going to be if we can be competitive away," Arsenal manager Unai Emery told reporters, repeatedly describing the tie as "50:50".
The Gunners tried to increase their advantage as the first half wore on but they failed to capitalise despite several shots on goal from strikers Alexandre Lacazette and Pierre-Emerick Aubameyang, while Napoli had Meret to thank for numerous saves.
Carlo Ancelotti's men poured forward at the start of the second half in search of an away goal, with striker Lorenzo Insigne's effort ruled offside and Koulibaly denied moments later when keeper Petr Cech tipped his header over the bar.
The game quickly opened up and Ramsey, who will join Napoli's rivals and Serie A leaders Juventus in the close season, and Nacho Monreal created chances at the other end but were unable to outwit Meret again.
Napoli went closest to scoring when Insigne raced down the right and crossed to Piotr Zielinski, but the Pole's right-foot effort shot up over the bar.
"We had our chances and wasted them. We know we didn’t have a good game. Now we have to think about the return leg," Insigne told Sky Sports.
"The away goal would have been vital. We have to stay focused, learn from our mistakes and have more courage next week," he said.
The Italian side have now failed to beat English opponents away from their San Paolo stadium in nine attempts in European competition, and will need to find some scoring form at home if they are to progress in the competition.
"I think the second half gave us some idea how we can play the second game," Ancelotti told reporters, suggesting his side had more of the run of play as Arsenal's players tired, a number of them pulling up with cramp as the game neared the end.
Benfica teenager Joao Felix nets treble in 4-2 Eintracht win
Benfica's 19-year-old forward Joao Felix became the youngest player to score a Europa League hat-trick as he led them to a 4-2 win over 10-man Eintracht Frankfurt in their quarter-final first leg on Thursday.
The Bundesliga side, who played with 10 men for almost an hour, were in danger of being blown away when Benfica went 4-1 up just after halftime but a second goal by substitute Goncalo Paciencia left the tie more finely balanced for the return.
Benfica coach Bruno Lage warned against getting carried away with the performance of Joao Fenix, who only made his first-team debut this season.
"If he hadn't scored tonight, everyone would have said he is off-form, but because he scored three, they say he is flying," said Lage.
"Let's take it easy, let him develop and enjoy himself. He has to go out and enjoy himself and that is what he has done. One day he will score three goals, the other he won't score any. He has to develop naturally."
Eintracht forward Luka Jovic, on loan from Benfica, missed two early chances as the Bundesliga side made a bright start before the game took a dramatic twist.
Joao Felix threaded a ball through the Eintracht defence to send Gedson Fernandes clear and he was pushed over from behind by Evan N'Dicka.
The referee judged that Fernandes had been denied a clear scoring chance, N'Dicka was sent off and Joao Felix calmly converted the penalty in the 21st minute.
Jovic equalised against his parent club in the 40th minute after Benfica were caught in possession but Joao Felix put the hosts back in front three minutes later with a low strike from 20 metres which caught keeper Kevin Trapp off guard.
Ruben Dias headed a third for Benfica after a corner was knocked on in the 50th minute and Joao Felix sidefooted the fourth four minutes later as the Eagles threatened to run riot.
Eintracht were not finished, however, and substitute Paciencia, raised at Benfica's arch-rivals Porto, put them back in the tie with a looping header from a corner in the 72nd.
"It feels like every shot they had went in despite me getting something on most of them," said Trapp. "It’s not a great feeling for a keeper because you’re the one that has the responsibility to come to your team’s rescue."
"We could have let our heads drop at 4-1, but we persevered and hopefully a 4-2 loss will be enough come the end of the second leg."
Late Alonso goal saves Chelsea
A late header by defender Marcos Alonso and Kepa Arrizabalaga's goalkeeping heroics helped Chelsea beat a stubborn Slavia Prague 1-0 in their Europa League quarter-final, first leg on Thursday.
Spaniard Alonso broke the deadlock for the west London side in the 86th minute when he sneaked behind two defenders to connect with Willian's cross and score what proved to be the winner in the first competitive meeting between the two sides.
"I'm very happy with the result and also with the performance, because at this moment we are able to suffer, in the past we were not," Chelsea manager Maurizio Sarri told reporters.
"In the past, when we were in trouble, we conceded immediately a goal, now we did not concede anything."
Sarri made seven changes from the team that beat West Ham United 2-0 in the Premier League on Monday, with talisman Eden Hazard coming off the bench for the last half an hour.
Willian's fierce shot hit the bar in the first half before the hosts had a chance to open the scoring on the counter in the 69th minute when Ibrahim Traore drive into the Chelsea box and struck a shot that was superbly punched away by Kepa.
The Spanish goalkeeper then kept out left-back Jan Boril's close-range shot in the 80th minute.
Alonso's goal gave the Blues a vital away goal as they put behind them bitter memories of the stadium where they lost the 2013 Super Cup to Bayern Munich in a penalty shootout.
Slavia defender Simon Deli said: “It’s disappointing because we did very well and in the last minutes we conceded this kind of goal. Of course, it’s difficult for us, but it’s football.
"Now we’ll prepare for our next game - the derby - and then against Chelsea in London,” he added referring to the Czech league leaders' game against third-placed Sparta on Sunday.
Last-gasp double puts Valencia in Europa League driving seat
Valencia scored twice in stoppage time to secure a 3-1 victory away to local rivals Villarreal and take the upper hand after the first leg of their Europa League quarter-final on Thursday.
The result was harsh on the home side, who largely dominated possession yet were unable to create clear-cut chances against Valencia, who sit 12 places and 16 points above them in La Liga.
They were made to pay as a quick-fire double at the death from Daniel Wass and Goncalo Guedes, his second goal of the match, left them with a mountain to climb in next week's return.
"We knew it was going to be tough and we did what we had to do," Guedes told BeIn Sports. "We know they have their strengths but we defended well and played on the counter and we were able to get our goals that way."
"I don’t think the result was undeserved. We had our chances, we were clinical and it is a deserved victory."
Portugal forward Guedes opened the scoring after six minutes. He was felled in the box by Santiago Caseres and, although Valencia skipper Dani Parejo's penalty was saved by Andres Fernandes, Guedes netted the rebound from close range.
It was the second consecutive game in which Parejo had missed a spot-kick after he failed to score against Rayo Vallecano in la Liga at the weekend.
After ceding the early advantage, Villarreal began to enjoy more of the ball, with Santi Cazorla causing problems for the Valencia backline.
Former Arsenal midfielder Cazorla, who himself missed a penalty at the weekend, equalised from the spot in the 36th minute after Ezequiel Garay clumsily brought down Vicente Iborra and English referee Michael Oliver pointed to the spot.
Samuel Chukwueze was twice denied by Valencia goalkeeper Neto after the break as Javi Calleja’s side looked to force a winner, but Villarreal gradually ran out of ideas and appeared happy to settle for the draw.
Yet with the clock having reached 90 minutes, Valencia's Wass produced a sweeping left-foot finish against the run of play following Jose Gaya's storming run down the left-hand side to stun the home crowd.
Guedes then rounded off the scoring with the last kick of the game after Denis Cheryshev -- a former Villarreal player -- led an electric counter-attack as Marcelino's side put one foot in the last four.
"We weren't savvy at all," said Calleja in his post-match news conference. "There's another game to play (after going 2-1 down), but we played like there wasn't one.
"Now, everything is more difficult. It's a tough result to take but if you gift up chances and don't take yours then Valencia are always going to do what they did.
"We won't give up, of course. We'll go to Mestalla next week wanting to win and restore pride," he added.