Pierre-Emerick Aubameyang scored a superb hat-trick to send Arsenal through to the Europa League final to face Chelsea after a clinical 4-2 win at Valencia (7-3 on aggregate).
Arsenal will play their London rivals in the final in Baku on May 29 after Chelsea's dramatic penalty shoot-out win over Eintracht Frankfurt, meaning four sides from the same country will contest the finals of Europe's two premier competitions for the first time ever.
Valencia halved the two-goal deficit from the first leg through Kevin Gameiro's close-range finish (11), but Aubameyang gave Arsenal further control in the tie with a fine half-volley shortly after (17).
Alexandre Lacazette then put the Gunners ahead on the night with a finish into the corner from 15 yards (50), meaning Valencia needed four, and they got one through Gameiro's bundled finish (58).
But Arsenal regained their advantage through Aubameyang's near-post finish (69), and the Gabon striker got his hat-trick and 29th of the campaign with a thumping effort from an acute angle (89).
Valencia: Neto (5), Gabriel (4), Gaya (5), Piccini (5), Garay (5), Guedes (6), Parejo (5), Coquelin (5), Wass (5), Gameiro (6), Rodrigo (6)
Subs: Soler (5), Torres (5), Mina (5)
Arsenal: Cech (6), Maitland-Niles (7), Sokratis (6), Koscielny (6), Monreal (6), Xhaka (6), Torreira (7), Kolasinac (6), Ozil (6), Lacazette (8), Aubameyang (10)
Subs: Mkhitaryan (7), Mustafi (6), Guendouzi (7)
Man of the match: Pierre-Emerick Aubameyang
How Arsenal overcame hostile atmosphere
Valencia raced out of the blocks and were ahead early on through Gameiro, who tapped home at the far post into an empty net from Rodrigo Moreno's low, deflected cross from the left after a devastating counter attack.
It should have been two as Rodrigo's shot hit his own man Gameiro from close range, before Rodrigo volleyed inches wide from 25 yards with a sublime effort, and Valencia were made to pay moments later during a rare Arsenal attack.
Former Gunners defender Gabriel's poor header allowed Lacazette to nod down for Aubameyang, and the Gabon striker's fine half volley from 18 yards found the bottom right corner past Neto.
Arsenal made four changes from the side which drew 1-1 with Brighton on Sunday; Cech was in for Leno, while Maitland-Niles, Koscielny and Kolasinac came in for Lichtsteiner, Mustafi and Mkhitaryan.
Valencia made two changes; Diakhaby and Mina came out, replaced by Garay and Gameiro.
Arsenal began to settle more and could have killed the tie off before the break as Aubameyang turned provider for Lacazette, but the Frenchman's first-time shot from 20 yards brushed the outside of Neto's left-hand post as he stood rooted.
Unai Emery's last 19 @EuropaLeague knockout ties:— Sky Sports Statto (@SkySportsStatto) May 9, 2019
✅v Valencia pic.twitter.com/vLY93hCuDx
The tie looked done and dusted as Lacazette put Arsenal ahead with a low finish into the bottom right corner from inside the box after Lucas Torreira's square ball, but Gameiro pulled one back from close range with a messy goal from Rodrigo's cross-shot.
Aubameyang then showed his superior quality again, however, turning up at the near post to get ahead of his marker and touch home Ainsley Maitland-Niles' fine cross from the right.
And with seconds remaining, Aubameyang got his hat-trick on the night and fourth against Valencia in the tie, powering into the roof of the net from the tightest of angles after Henrikh Mkhitaryan's cute ball.
Unai Emery insists Arsenal have had no success yet...
"It's not finished yet, there's no success yet, we have to play the final," said the Arsenal boss. "We are happy but we know that it continues to be difficult to win.
"We can be proud of the players, the work, the supporters here today with us. These two matches [Napoli in quarter-final and Valencia] were not easy and the mentality was perfect. We showed everyone today our character."
Aubameyang was the inspiration as Unai Emery reached his fourth Europa League final in five years.
Nick Wright rounds up the main talking points from their fine victory at Mestalla...
- Arsenal have qualified for their seventh European final (1 Fairs Cup, 3 Cup Winners Cup, 1 Champions League, 2 UEFA Cup/Europa League), lifting the trophy on just two of the previous six occasions.
- Arsenal registered a win away to Spanish opposition for the first time in eight games (D2 L5), since a 1-0 win at Real Madrid in February 2006.
- Arsenal's Pierre-Emerick Aubameyang has netted 29 goals in all competitions this season, a haul only Sergio Aguero (31) can better among Premier League players.
- Since his Arsenal debut in August 2017, Alexandre Lacazette has been directly involved in 51 goals for the club in all competitions, more than any other player (36 goals, 15 assists).
- Excluding own-goals, 11 of Arsenal's last 12 Europa League goals have seen Alexandre Lacazette and Pierre-Emerick Aubameyang involved (four goals and one assist for Lacazette and six goals and two assists for Aubameyang).
McCoist: Emery could get away with defeat
Speaking on The Debate, Ally McCoist says Unai Emery can afford to lose the Europa League final, but it's a different story for Maurizio Sarri.
"I think Emery, even if he loses the final, has seen a good improvement in Arsenal. He knows what he needs to do, strengthen defensively, and he'll get away with it.
"There has been more pressure on Sarri with one or two things not going his way. He could end up winning the Europa League and finishing third, and you'd have to say that's a fantastic season for Chelsea."
When is the Europa League final?
The Europa League final, the 10th in its current format and 48th overall of Europe's second-tier competition, will take place on May 29, 2019.
Kick-off is at 8pm (BST), 9pm (CEST). The Olympic Stadium in Baku, the capital of Azerbaijan, will host the final.
Arsenal now go to Burnley on Sunday at 3pm in the Premier League, with a slim chance of making the top four, while Valencia host Alaves on Sunday at 5.30pm in La Liga.