Arsenal qualified for the last 32 of the Europa League after a match marred by forward Danny Welbeck suffering what appeared to be a serious ankle injury.
The Gunners were held to a goalless draw by Portuguese side Sporting Lisbon at Emirates Stadium to join Chelsea in the next phase.
Sporting ended the game with 10 men when ex-Barcelona defender Jeremy Mathieu was shown a straight red card after fouling Pierre-Emerick Aubameyang when he was clean through on goal – although the hosts could not find a winner.
But the fixture was overshadowed by the injury to England international Welbeck, who was carried off on a stretcher.
The 27-year-old was hurt in the 25th minute when he jumped for a header and landed badly on his right ankle.
He received oxygen and had his leg in a protective brace as he was taken off the pitch, with up to 10 medical staff around him as he received treatment.
Some of his team-mates were also visibly affected by the incident.
Welbeck has scored five goals this season, played for England against Spain in September and had been named in Gareth Southgate’s latest squad for the friendly with the United States and the Nations League match against Croatia.
Former Arsenal defender Martin Keown, working as a pundit for BT Sport, said: “Danny has had two major injuries to his knee and he tried to plant his foot and got it stuck behind him.
“He is a great player and good for that group as he is 27, one of the older players. He will be a big loss for them. It looks like he will be out for a while.”
Gunners extend unbeaten run
Arsenal, who are fifth in the Premier League and now unbeaten in 15 games, have 10 points from their opening four Europa League games.
A 1-0 win for Azerbaijani side Qarabag over Vorskla Poltava of Ukraine in the other Group E match was enough to take the Gunners through to the knockout phase.
Unai Emery’s side are three points clear of Sporting Lisbon in second and will win the group with victory at Vorskla Poltava on Thursday, 29 November.
After winning their opening three Europa League games, Emery was able to make nine changes from the side that drew 1-1 with Liverpool on Saturday. Only Rob Holding and Henrikh Mkhitaryan kept their places, with Mesut Ozil, Alexandre Lacazette, Granit Xhaka and Hector Bellerin left out completely.
Top scorer Aubameyang started on the bench but came on as a first-half substitute for Welbeck.
Aubameyang hit the bar early in the second half and later saw his goal-bound shot blocked by former Liverpool defender Sebastian Coates.
Mathieu was dismissed in the 87th minute for fouling the Gabon striker, who fired the resulting free-kick over the bar.
There was another injury problem for the Gunners in the second half as right-back Stephan Lichtsteiner pulled up with what appeared to be a hamstring problem on a mixed day for the club.
A rare off night in front of goal – stats
- Arsenal failed to score for just the second time under Emery – they also drew a blank against Manchester City in the Spaniard’s first game in charge (0-2).
- Sporting failed to have a shot on target in both matches against the Gunners this season.
- Excluding qualifiers, Arsenal have kept three consecutive clean sheets in European competition for the first time since the 2007-08 Champions League group stages.
- Sporting kept their first away clean sheet in the Europa League since September 2011 (2-0 vs FC Zurich), ending a run of 18 games in which they had conceded.
- Aubameyang had twice as many shots as any other Arsenal player (four), but none were on target.
Arsenal return to Premier League action on Sunday when they entertain Wolves (16:30 GMT kick-off).
The Gunners are next in Europa League action on 29 November, away at Vorskla Poltava (17:55), with Sporting travelling to play Qarabag at the same time.
More to follow.