Dramatic Arsenal defeat comes at a cost for Mikel Arteta
The Gunners were made to pay for it too, going all the way to penalties before losing 5-4. Gabriel Martinelli missed his and Sporting slammed all five home.
Before that, just like in the first leg, the two sides could not be separated and they were level at 1-1 at the end of normal time.
Granit Xhaka had given his side the lead in the first-half with his first goal since October, but Sporting levelled after the break through a stunning strike from Pedro Goncalves.
They were two moments of real quality in an otherwise frantic game, and Arteta will be disappointed with this display.
Arsenal have been knocked out of the Europa League at the last-16 stage and Arteta will be wondering at what cost. His squad had to play 120 minutes and they must quickly recover to welcome Crystal Palace on Sunday.
To make matters worse, Takehiro Tomiyasu and William Saliba were both forced to come off injured inside the opening 22 minutes here. Arteta had spoken pre-game about how he now calls substitutes “impacters”, however he would not have wanted to throw Ben White and Rob Holding on this early.
The possible loss of Saliba will be of the greatest concern to Arsenal. They are five points clear at the top of the Premier League and can extend that lead to eight if they beat Palace on Sunday.
Arteta was adamant that Arsenal wanted to compete to win both the Europa League and Premier League this season – and his team selection for this second leg underlined that.
Only Bukayo Saka, Martin Odegaard, Thomas Partey and White were missing from the ‘first XI’ as the home side looked to improve on last week’s showing in Lisbon, which ended 2-2.
That game was chaotic and there were shades of that here too, with Sporting having joy early on. Indeed, after 15 minutes, they had over 60 per cent of the possession.
Arsenal slowly grew into the game, with Gabriel Jesus showing some nice flashes on his first start since November.
There was clearly signs of rust from the Brazilian, who has been out for three months after knee surgery in December, but there were bright sparks too.
It was another Gabriel, though, who eventually helped Arsenal get in front. Martinelli was picked out by Jorginho’s pin-point through-ball and, when his shot was saved, Xhaka was there to smash the ball home.
The goal was the Swiss’ first since October and it was a timely one as it put Arsenal 3-2 ahead in the tie.
You suspected Arsenal would kick on from there, but it was Sporting who fought back into the match. Especially in the second-half, Ruben Amorim’s side disrupted the rhythm of the game and unsettled Arsenal.
They got the equaliser they deserved as well and in bizarre fashion. Jorginho played Xhaka into trouble by the halfway line and the ball broke to Goncalves.
The midfielder looked up and saw Aaron Ramsdale off his line, beating him from just inside the Arsenal half.
That goal gave you the sense it may not be Arsenal’s night and extra-time only underlined that feeling.
Leandro Trossard hit the post. Gabriel drew a stunning save from Adan and then had another header cleared off the line.
Sporting then put in a flawless performance in the shootout, with Ramsdale twice missing good chances to make saves.
He and Arsenal were punished as Martinelli missed to send Sporting through. Joy for Lisbon, but despair for London.