Arsenal came back to whip Cologne 3-1
Alexis Sanchez scored a stunning goal as Arsenal came from behind to beat Cologne in a controversial Europa League match delayed for an hour following crowd trouble.
Chilean Sanchez, who nearly left the club to join Manchester City on transfer deadline day, picked the ball up outside the area and curled a shot past keeper Timo Horn.
The game did not begin until 21:05 BST as thousands of visiting supporters arrived at the ground without tickets and then clashed with stewards inside the Emirates Stadium.
When the match did get under way, Cologne took the lead in spectacular fashion as Jhon Cordoba lobbed fellow Colombian David Ospina from 40 yards.
Striker Olivier Giroud planted a header wide of goal from six yards for the much-changed home side, who were booed at the half-time whistle.
But substitute Sead Kolasinac equalised with a thumping volley before Sanchez struck, and Hector Bellerin then added the third from close range, as midfielder Jack Wilshere made his first appearance for the club since August 2016.
In Group H’s other game, Red Star Belgrade drew 1-1 against BATE Borisov.
Silva hits hat-trick as AC Milan crush Austria Vienna 5-1
Andre Silva scored a hat-trick as AC Milan began their Europa League campaign by thrashing Austria Vienna 5-1.
Silva was signed from Porto for £34m by Milan, who are competing in Europe for the first time in four years.
The Italians spent around £170m in the summer and new recruit Hakan Calhanoglu put them ahead with a thumping drive. Ex-Liverpool player Suso netted the fifth after Silva’s treble.
Defender Alexandar Borkovic powerfully headed in from a corner for Vienna.
Turkish midfielder Calhanoglu – bought for £22m from Bundesliga side Bayer Leverkusen – ran the game for Vincenzo Montella’s side, providing two assists in addition to his goal.
BBC Sports reports that Milan host Udinese in Serie A on Sunday, after being thrashed 4-1 by Lazio in their last domestic outing.