Alexis Sanchez's first goal for Arsenal ensured his new club will be included in pot one for Thursday's Champions League draw, after Arsene Wenger's side narrowly beat Besiktas in their play-off second leg.
Sanchez's strike on the stroke of half-time was the only goal of the game as Arsenal saw off a stubborn Besiktas side in what was a nervy night for the hosts at the Emirates Stadium.
- Man of the Match: After being dragged off at half-time in Saturday's lacklustre draw with Everton, Alexis Sanchez came out with what appeared to be a rocket up his bottom. It worked - he ran the Besiktas line ragged all night and finally got the goal he's so desperately needed.
- Villain: For the second time in two matches against Besiktas, Arsenal had to hold on with 10 men. Mathieu Debuchy saw red for a criminal pull back on half-way which could so easily have cost his team dear.
- Key Moment: Only one winner here - take a bow, Sanchez. Winning comes down to scoring goals and the Chilean showed superb composure to net his first for the club at such a crucial time in the match. It changed the whole mood around the Emirates.
- Rob Bartlett
For the second successive match against the Turkish side, Arsenal finished with 10 men on the pitch as summer signing Mathieu Debuchy was sent off with 15 minutes to go.
Wenger's team missed a succession of chances to put the qualifier beyond the reach of Besiktas following a goalless draw in the first leg in Istanbul.
Sanchez, Santi Cazorla and Alex Oxlade-Chamberlain failed to score when it was harder to miss amid the mayhem of a roller-coaster second half.
Frantic Arsenal almost paid the ultimate price as they were over-run time and again by Besiktas who sought the away goal that would secure a prized European scalp.
The Turks' coach Slaven Bilic, sat in the stands due to his touchline ban for arguing with referee Milorad Mazic in the first leg, watched as Demba Ba crashed a great chance into the side netting.
It was the best of Besiktas' opportunities, although Bilic was furious that a penalty was not awarded when Ramon Motta appeared to be clipped from behind by Jack Wilshere.
Sanchez's goal on the stroke off half time enabled Arsenal to progress into the Champions League proper for a 17th successive season, but they rode their luck against spirited opposition to subject their fans to a nail-biting night.
The summer signing from Barcelona operated as the lone striker in the absence of Olivier Giroud, who has been ruled out until the New Year with a tibia injury.
And while Sanchez struck the all-important winner that guarantees Arsenal's presence in the draw for the group stage, he was also wasteful.
The home side should have taken an early lead after he was nudged over and referee Pedro Proenca played advantage, but Wilshere sent a fine chance wide of the right post.
The early onslaught continued with Cazorla failing with an audacious lob and Sanchez proving unable to reach the ball after Oxlade-Chamberlain had sped free down the right.
Ba threatened to collect a long ball at the other end with only Wojciech Szczesny to beat, but the Poland keeper arrived at the critical moment.
Sanchez sent a free-kick into the arms of Tolga Zengin before Mathieu Debuchy and Ersan Gullum collided in mid-air with a thud. The Turks were defending resolutely, crowding Sanchez out as the Chile winger attempted to capitalise on a floating pass by Oxlade-Chamberlain.
And they threatened in attack too as Motta teed up a shot after gathering a cut back only to crash to the ground following a challenge by Wilshere in the area. Replays proved inconclusive over the extent of any content, but Proenca was satisfied there was no penalty, drawing howls of protest from the noisy contingent of Besiktas fans.
A poor first touch from Sanchez prevented him from making the most of Wilshere's deft pass, but on the stroke of half-time the South American opened his Arsenal account.
Besiktas failed to clear the ball properly and Mesut Ozil combined with Wilshere, who left the German's final ball for Sanchez to guide into the net.
Having just ridden their luck in their own area, the goal came as an enormous relief and Sanchez was mobbed by his jubilant team-mates.
Sanchez was a metre away from making it 2-0 five minutes after the interval but he was beaten by the speed of Cazorla's pass and he should have done better moments later when set up by Wilshere.
Still Arsenal's defence could not rest, however, as successive raids into their area were met with scrambling responses. The point was emphasised when Ba smashed a brilliant opportunity into the side netting knowing he should have done much better.
Cazorla hit the right post and with Besiktas caught on the counter, somehow Sanchez and Cazorla failed to put the match beyond the visitors' reach.
Debuchy received his marching orders, if a little unfairly as he won the ball in the tackle, and from then on Arsenal defended for their lives in a hair-raising finish.