ARSENAL swept away memories of their awful start to the season as a Robin van Persie double powered the Gunners into the last 16 of the Champions League.
Van Persie hoisted his season's tally to 17 with a header on 48 minutes and a tap-in five minutes from the end.
That saw off a Borussia side who battled hard during the first half but eventually had no answer to Aaron Ramsey's midfield skills and Van Persie's hunger for goals.
And ecstatic Emirates fans will surely have forgotten any talk of early retirement for manager Arsene Wenger, even though Borussia pulled back a goal in time added on.
Arsenal went into the game in high spirits on the back of five straight Premier League victories.
But Dortmund, who beat Bundesliga leaders Bayern Munich on Saturday, were in no mood to be overawed and fired in the first shot on target when Shinji Kagawa forced a save from Gunners keeper Wojciech Szczesny.
Arsenal legend Thierry Henry, sitting in the Emirates stands alongside tennis star Roger Federer, saw the club's current goal idol Van Persie return the compliment in the 10th minute, with Roman Weidenfeller saving his shot.
But the Londoners, who drew 1-1 in Dortmund in September, had the best chance of the match on 20 minutes when Ramsey released Theo Walcott with a brilliant ball down the right. Weidenfeller raced out to save at the Arsenal man's feet.
With Arsenal showing signs of settling into their game, Dortmund suffered a setback when midfielder Sven Bender was injured and replaced by 18-year-old Moritz Lietner.
Soon after, Dortmund were forced into another midfield change when Mario Gotze went off to be replaced by Ivan Perisic.
Nevertheless, the Germans continued to harry Arsenal in the middle third, denying them a platform to carve out chances.
Wenger's men had the ball in the net on 40 minutes, but 'scorer' Walcott was clearly offside from van Persie's pass.
Borussia flared into life as the first half moved into time added on, but a timely tackle by Alex Song snuffed out the threat as the visitors threatened down the right.
Gunners fans could be forgiven for wondering just when the fireworks would start as half time arrived in a match short on goalmouth action but heavy on tension.
Borussia looked the more threatening at the start of the second half as Kagawa again forced a save from Szczesny.
But the moment Gunners fans had been praying for came just over a minute later as the ever-patient Ramsey started the move that unlocked Borrusia's stubborn defence.
Ramsey, midway in the Germans' half, played the ball back to Song who raced off down the left on a brilliant run that took out three defenders.
The Cameroon star set himself up for a perfect cross to the far post where Van Persie was waiting with a classic downward header that bounced past Weidenfeller with such power that the ball hit the roof of the net before nestling safely for the goal that fired Arsenal's hopes of reaching the knockout stages.
Marcel Schmelzer's exasperation boiled over as he clashed with Ramsey on the touchline, and soon after the Dortmund left back was booked for a foul on Walcott.
With Wales captain Ramsey doing most of the prompting, the match was opening out, and Gervinho could have scored a second on the hour after being put through by Van Persie.
But the ball was whipped off his toe by Mats Hummels as he was about to shoot.
Three Arsenal men — Ramsey, Walcott and Yossi Benayoun — were booked as Dortmund battled to get back into the game.
But there was no way back on 85 minutes when Per Mertesacker headed on a corner to give van Persie a tap-in at the far post.
Kagawa netted in the 91st minute — but it really didn't matter as the Emirates party was well under way.