Arsenal's hopes of a Europa League run were dashed in cruel style after a last-minute Youssef El Arabi goal put Olympiakos through to the last 16 of the Europa League.
Pierre-Emerick Aubameyang had looked like he had rescued Mikel Arteta's Gunners with a magnificent scissor kick seven minutes from the end of extra time put them in the driving seat.
The Gunners striker had levelled to make it 1-1 on the night, cancelling out a 53rd-minute goal from Papa About Cisse.
However, El Arabi's late strike clinched the tie, making it 2-1 on the night to the 44-time Greek champions after, what has to be said, was a lacklustre showing from the home side.
Aubameyang had missed a gilt-edged chance moments before the end of extra time when it seemed easier to score, but the Gabon striker couldn't work his magic at the finale of a gruelling contest.
Arsenal boss Arteta 'hurt' by knockout
Despite losing 1-0 to Arsenal in Greece last week, El Arabi's late goal made it 2-2 on aggregate, meaning the away side won the tie on away goals.
A bitterly disappointed Arteta said after the match: "It hurts. It would have been a beautiful tournament to win.
"We had an incredible opportunity to win at the end. It's a big disappointment [but] we move forward together. Football is cruel.
"The boys are exhausted after four games in 11 days. We weren't ruthless enough but that's football. I just want to get the boys belief back."