Arsenal suffered a disastrous 3-1 defeat in a hostile atmosphere against Ligue 1 side Rennes.
The Gunners took an early lead through Alex Iwobi and appeared to be in control of the game until Sokratis Papastathopolous was sent off for two bookable offences. Benjamin Bourigeaud smashed home the resulting free-kick, and an own-goal from Nacho Monreal gave the French outfit the advantage.
In the game's dying moments, Ismaela Sarr set the seal on the result with a crashing header. Arsenal's Europa League hopes are now left hanging by a thread.
There was much to like about Arsenal's first-half display. The movement and interplay between Iwobi, Mesut Ozil and Pierre-Emerick Aubameyang had Rennes on the ropes. Unfortunately, once they went down to 10 men they could not sustain that kind of threat and were defensively exposed.
Given their first-half performance, Arsenal will feel frustrated to be so heavily behind in the tie. There will be plenty of blame aimed at the officials, who not only sent off Sokratis with a harsh second yellow, but also incorrectly raised an offside flag against Aubameyang when he was clean through on goal.
However, Arsenal also need to look at themselves. They did not manage the game well and were guilty of getting caught chasing an equaliser when Rennes scored their third goal.
Manager rating out of 10
5 -- Unai Emery's substitutions in this game were a little bizarre, and his decision to leave Henrikh Mkhitaryan on at right-back for an entire half will doubtless lead to some criticism. He has a huge task now to overturn this scoreline.
Player ratings (1-10; 10 = best. Players introduced after 70 minutes get no rating)
GK Petr Cech, 7 -- It will have been an emotional night for Cech, who was afforded a chance to return to his former club in what will be his final season. It's fair to say he had no chance with Bourigeaud's equaliser, and in the second half he produced a number of good saves to keep the scoreline down.
DF Shkodran Mustafi, 6 -- The German endured a difficult first half, twice having to have treatment for what appeared to be a thigh injury. However, he managed to stay on and might have had a goal when his shot fizzed just wide of the left-hand post. Once Sokratis went off, he switched to a more familiar role at centre-half. To be frank, he was no better there.
DF Laurent Koscielny, 6 -- This seemed like an opportune game in which to rest Koscielny. The fact he played showed that Emery was determined not to underestimate Rennes. Arsenal fans will hope he can be fit enough to start a third game in a week against Manchester United on Sunday.
DF Sokratis Papastathopolous, 5 -- Arsenal fans have taken to Sokratis but even his biggest fans would admit he treads a disciplinary tightrope at times. Although his second booking appeared harsh, he seemed a little overheated right from kickoff. Arsenal are right to expect more from their experienced centre-half.
DF Nacho Monreal, 5 -- Once again, Emery opted for Monreal over Sead Kolasinac. It seems that when playing with four at the back away from home, the coach prefers to opt for more defensive full-backs. Rennes looked to exploit this flan with the pace of Sarr, but he got little change out of the Spaniard in the first half. The second half was a different story, and Matteo Guendouzi was brought on to give Monreal some much-needed protection. He was the unfortunate man who scored an own goal.
MF Granit Xhaka, 6 -- Emery opted for the experience of Xhaka rather than starting Guendouzi, and in the first half the Swiss international justified his selection with a commanding performance in the heart of the midfield. However, he struggled in the second period as Arsenal were overrun.
MF Lucas Torreira, 5 -- The Uruguayan ought to have doubled Arsenal's lead inside the first 15 minutes, but his side-footed effort from an Iwobi cut-back was too close to the goalkeeper. Quite why he was so high up the field in the 87th minute when Rennes broke for their third goal is anyone's guess.
MF Henrikh Mkhitaryan, 6 -- The former Manchester United man deserves huge credit for filling in at right-back for most of the second half. He wasn't particularly bad, but surely there was a more sensible option for Emery?
MF Mesut Ozil, 6 -- The German had some good touches in the first half, but it was no surprise when he was sacrificed for Aaron Ramsey.
MF Alex Iwobi, 7 -- It was Iwobi who opened the scoring when his attempted cross curled into the far corner. The Nigerian's fifth goal of the season makes it his most prolific campaign to date. Shortly afterward, he might have had an assist, but Torreira could not convert his cutback pass from the left. He was unfortunate to be sacrificed for Guendouzi in the 53rd minute.
FW Pierre Emerick-Aubameyang, 5 -- After his penalty miss in the north London derby, Aubameyang owed the Arsenal fans a big performance tonight. Sadly, it was not forthcoming. While Aubameyang's pace and movement certainly troubled the Rennes backline, his execution of final ball and shooting certainly left something to be desired.
MF Matteo Guendouzi, 6 -- Came on for Iwobi (53) and was a busy figure in the midfield.
MF Aaron Ramsey, NR -- The midfielder came on for Ozil (70) but ended up playing as the team's most advanced player.
MF Sead Kolasinac, NR -- Introduced for Aubameyang (79) but didn't have much time to impact the game.