Aston Villa have their Premier League survival in their own hands when they play their final match of the season at West Ham on Sunday.
Dean Smith's side are out of the relegation zone following Watford's defeat by Manchester City and Trezeguet's potentially priceless strike means they have a better goal difference than relegation rivals Watford and Bournemouth.
Mikel Arteta's Arsenal are no certain to finish outside the top six for the first time in a quarter of a century.
They failed to follow unlikely victories against champions Liverpool and Manchester City in Saturday's FA Cup semi-final with a third win in a week as a much-changed line-up looked sluggish at best.
This Arsenal squad lacks a cutting edge when they need to break down defensive teams and a banner trailed by a buzzing plane overhead betrayed the club's American stewardship under owner Stan Kroenke. 'Back Arteta Kroenke Out' it read.
Villa were never going to be easy opponents with so much at stake - £200m by their chief executive’s calculations - however, and they played very well.
The crucial goal came after 27 minutes when a Conor Hourihane corner was touched on by Tyrone Mings and Trezeguet drove in a blistering right foot shot from the edge of the area. Keeper Emi Martinez had no chance but was not helped by the half-hearted block attempt from a turning Cedric.
Arsenal still have a say in who goes down as they host Watford in Sunday's all or nothing fixture list.
Arteta made expected changes after the exertions of the previous matches. Six different players started as he recalled Lucas Torreira, Rob Holding, Cedric, Eddie Nketiah, Sead Kolasinac and Bukayo Saka.
At least Arteta affirmed what he probably already knew in that Granit Xhaka is his most important central midfielder. What fit again Mesut Ozil learned after again being left out of the squad entirely, behind untested teenager Matt Smith, is anyone's guess.
The German's only comment in recent weeks on his Twitter account, which has 24.9m followers was to announce he is ready to play, and a new partnership with a shoe manufacturer.
Arteta insists he will be treated on merit, like any other player in his squad and the word from the player's camp is he wants to fight for his place next season amid recent interest from Turkish star-studded champions Istanbul Basaksehir and rival Super Lig sides Galatasaray, Besiktas and Fenerbahce.
Arsenal's key midfielder now is Xhaka, himself an outcast earlier this season when he was booed off by his own fans and stripped of the captaincy by former manager Unai Emery.
Arteta has got the Switzerland captain back to his best and sent him on for the start of the second half for Torreira.
Villa, sensibly, did not sit on their lead and rightly sensed ait was better to try to attack a vulnerable looking Arsenal side Arsenal picked up the tempo too, however, and Villa looked fragile as Cedric and Bukayo Saka threatened from the wings. Pierre-Emerick Aubameyang had one of their best effort blocked.
Arteta made what he hoped would be a decisive move with barely 60 minutes gone when he sent on Nicolas Pepe and Kieran Tierney for Saka and David Luiz.
Smith's unchanged lined up, were led by a back in form Jack Grealish, who could have played his last game at Villa Park ahead of a summer transfer.
He played with the passion he has as a Villa fan and was at the heart of a spirited second half display.
Substitute Keinan Davis should have secured all three points with 15 minutes to go when he was sent clear by a great Grealish pass and dragged a nervy looking shot wide of a post.
Villa's luck held good when Eddie Nketiah's header bounced off the inside of a Villa post in the very next attack.
Arsenal were far from going through the motions and did everything to try and get a goal, but they had little by the way of a potent threat and Smith survived the nerves from the touch line to record a rare win.
Reina 6, Elmohamady 5 (Guilbert 25), Konsa 6, Mings 6, Targett 5, McGinn 7 (Lansbury 90), Luiz 6, Hourihane 6 (Nakamba 73), Trezeguet 6, Samatta 5 (Davis 72), Grealish 7.
Substitutes: Nyland, El Ghazi, Jota, Hause, Vassilev.
Martinez 6, Holding 6, Luiz 6 (Tierney 60), Kolasinac 5, Cedric 5 (Willock 79), Ceballos 5, Torreira 5 (Xhaka 45), Saka 5(Pepe 60), Nketiah 6, Lacazette 5, Aubameyang 5.
Substitutes: Macey, Bellerin, Sokratis, Maitland-Niles, Smith.
Ref: Chris Kavanagh