Francisco Moura's second-half strike earned hosts Porto a 1-1 draw against 10-man AS Roma in the first leg of their Europa League knockout round play-off on Thursday.
Manchester United were handed a tricky Europa League last 16 tie against Real Sociedad while Tottenham Hotspur will play Dutch side AZ Alkmaar after the draw was held on Friday, but both managers are more concerned about their Premier League form.
A round-up of Thursday's Europa League Round of 16 second leg matches.
United climbed to fourth in the standings on 15 points going into the last round of matches, in a strong position to reach the knockout phase along with Spurs who are sixth with 14 points.
IMAGES from the Europa League matches played on Thursday
AS Roma secured their place in the Europa League last 16 with a 3-2 home win over 10-man Porto on Thursday thanks to a Paulo Dybala double, advancing 4-3 on aggregate.
Arsenal defeated London rivals Chelsea 1-0 for their first win in four Premier League games on Sunday as a headed goal by stand-in striker Mikel Merino boosted their faint hopes of catching up with runaway leaders Liverpool.
London sides Tottenham Hotspur and Arsenal made winning starts as did fellow Premier League club Leicester City.
New AZ Alkmaar coach Dick Advocaat suffered a 1-0 defeat at former club PSV Eindhoven on his comeback to management in the Dutch league on Saturday.
A summary of Sunday's action in the Premier League.
Lazio, who had won all four previous games, were held to a frustrating scoreless draw by a Bulgarian side who came to defend.
AZ Alkmaar clinched their second Dutch championship after Ajax Amsterdam failed to beat PSV Eindhoven on Sunday.
IMAGES from the Europa League matches played on Thursday
PSV Eindhoven brushed aside Roda JC Kerkrade 3-0 to edge clear at the top of the Dutch league on Saturday.
AZ Alkmaar suffered a first European home defeat in their history and were eliminated from the UEFA Cup on Thursday after a 3-2 loss to Everton. The Dutch side had gone 32 games unbeaten at home in Europe since entering European competition in 1977.
Images from the Europa League semi-final first leg matches on Thursday.
Ukraine champions Shakhtar Donetsk dented Sevilla's bandwagon as the UEFA Cup holders wobbled before securing a 2-2 draw.
Manchester City celebrated their Premier League title on Sunday, beating Chelsea 1-0 with an early goal by Julian Alvarez in the team's home finale at a sun-drenched Etihad Stadium.
Spurs striker Bergwijn is major casualty as Netherlands trim squad
Seven-time European champions AC Milan hit back from two goals down against Celtic to claim a 4-2 victory that sent them into the Europa League knockout phase on Thursday as they were among 14 teams to progress in Europe's second-tier competition.
Harry Kane netted his 200th goal for Tottenham Hotspur as they won 3-1 at Ludogorets and AC Milan's 24-match unbeaten run ended
United captain Jesse Lingard fired them ahead in the 10th minute with a fizzing low shot from 20 metres before Dmitri Shomko and a Di'Shon Bernard own goal turned the match on its head shortly after half-time.
Tottenham Hotspur have signed Netherlands striker Vincent Janssen from AZ Alkmaar on a four-year contract, the Premier League club said on Tuesday. The 22-year-old finished his first top-flight season as the highest scorer in the Dutch league by racking up 27 goals to lead AZ to fourth in the table and a place in the Europa League next season.
Arsenal's young guns continued to shine as they dismantled Standard Liege 4-0 on a hectic night of Europa League action that produced a full house of Spanish victories on Thursday. A summary of the matches.
Having seen the domestic league and cup double go to Porto last term, Benfica missed a string of chances against PAOK in a one-sided first half as they enjoyed 72% of possession.
On a good night for English clubs in the Europa League, Manchester United hammered AZ Alkmaar 4-0, while Wolverhampton Wanderers also thrashed Besiktas 4-0 in Group K, and Arsenal came from two goals down to draw 2-2 away to Standard Liege and finish first in their pool. The upset of the night came in Group J as Crivelli scored a 90th-minute winner against Borussia Moenchengladbach to send Basaksehir through and knock the Germans out, with AS Roma grabbing the runner-up spot thanks to a 2-2 home draw with Wolfsberger as the Europa League group stage concluded on Thursday.
Netherlands Coach Marco Van Basten named a 23-men squad on Sunday for next month's World Cup finals in Germany.
Kazakhstan's Astana fought back to beat a youthful Manchester United side 2-1 at home, Arsenal's woes continued as Frankfurt's Daichi Kamada scored twice to secure a 2-1 win.
Manchester United breezed into the next round with a 6-1 aggregate win over Club Brugge
The Group L fixture, to be played under tight security in the Serbian capital, comes after England's black players suffered racist abuse at their Euro 2020 qualifier at neighbouring Bulgaria on October 14.
Manchester United, winners of the competition in 2017, will have a lot of travelling to do to Eastern Europe after being drawn alongside Kazakhstan side Astana, Serbia's Partizan Belgrade and Dutch side AZ Alkmaar.
Arsenal teenager Bukayo Saka scored his first goal for the club as they beat 10-man Eintracht Frankfurt 3-0, while Manchester United's 17-year-old Mason Greenwood secured a 1-0 win over FC Astana as the Europa League group stage began on Thursday.
Napoli kept alive their hopes of advancing from Group C after Lorenzo Insigne, Victor Osimhen and Matteo Politano secured a 3-0 home win over Legia Warsaw.
Athletic Bilbao and Atletico Madrid overcame German opposition to reach the Europa League semi-finals on Thursday while fellow Spaniards Valencia joined them by demolishing AZ Alkmaar.
Holland boss Louis van Gaal is at the top of Tottenham's wish list to fill their vacant manager position after the sacking of Andre Villas-Boas, according to reports.
Troubled Liverpool conceded a last-gasp goal in a 1-1 draw at Olympique Lyon Wednesday, leaving them in danger of an early Champions League exit, while Inter Milan were on the right end of some late drama. Arsenal, inspired by two goals from Cesc Fabregas, thrashed AZ Alkmaar 4-1 and virtually ensured their place after becoming the only Premiership side to manage a win this week.
Rubin Kazan, Udinese, Bruges and AZ Alkmaar qualified for the Europa league knock-out stages on Thursday and will go into the draw for the round of 32 with big guns Manchester United and Manchester City after their Champions League elimination.
A factbox on new Manchester United manager Louis van Gaal.
Tottenham Hotspur's Europa League hopes were crushed by mid-table Belgian side Gent, who booked their spot in the last 16 with a 2-2 draw at Wembley on Thursday as the hosts paid the penalty for Dele Alli's first-half red card.
Ajax closed the gap with Dutch league leaders Twente Enschede to one point after Luis Suarez and Marko Pantelic earned them a 2-0 win at struggling Willem II Tilburg on Wednesday.