Aston Villa climbed out of the Premier League relegation zone with a priceless 1-0 win against Arsenal, while Watford were thrashed 4-0 at home by Manchester City on Tuesday, taking a double blow to their relegation fate.
Arsenal, who failed to have an effort on target, can now finish no higher than eighth and their only route into Europe will be by winning the FA Cup against Chelsea on August 1.
Villa were struggling to find any rhythm as the game kicked off, but the drinks break offered Dean Smith a chance to fire up his players.
Crucially, Arsenal's long-standing weakness at set-pieces reared its head again as Villa snatched the lead in the 27th minute.
Tyrone Mings glanced Conor Hourihane's corner across the six-yard box and Trezeguet was left unmarked to blast a fierce strike past Arsenal keeper Emiliano Martinez.
The goal proved enough for Villa to move above Watford on goal difference as they have 34 points and a -26 goal difference with Watford also on 34 but with a -27 goal difference.
Trezeguet kisses the pitch after the Premier League match between Aston Villa and Arsenal at Villa Park in Birmingham, England, July 21, 2020. /VCG
"It was unbelievable, I think it was deserved we were outstanding today," Villa midfielder Jack Grealish, who was superb throughout, told Sky Sports.
"It's been a tense day, all we can do is focus on ourselves. It's up to us what we do on the last day. It feels massive to be out of the relegation zone."
Villa head to West Ham for their final game of the season on Sunday, while Watford visit Arsenal and second-bottom Bournemouth, three points from safety, travel to Everton.
There are a multitude of permutations that could decide relegation, but Villa will be safe if they can better Watford's result on what is certain to be a dramatic finale.
Watford goalkeeper Ben Foster admitted the Hornets' confidence is "crazy low" as they slipped into the relegation zone with one game of the Premier League season to go after being thrashed 4-0 at home by Manchester City on Tuesday.
Raheem Sterling of Man City during the Premier League match between Watford and Manchester City at Vicarage Road, Watford, England, July 21, 2020. /VCG
Raheem Sterling scored twice in the first half before Phil Foden and Aymeric Laporte rounded off a comprehensive City win.
"I don't think we helped ourselves, I don't think we did enough to do anything but what the result suggested to be honest," said Foster, who helped Watford keep the score down with a string of saves.
"The confidence is so crazy, crazy low. I don't know why it should be, but you get into a state of trying to minimize as much damage as you can and it's a dangerous way to do things."
City will end the season in second place no matter what happens on the final day when they host already relegated Norwich.
(With input from agencies)
(Cover image: Trezeguet of Aston Villa celebrates after he scores his side's first goal during the Premier League match between Aston Villa and Arsenal at Villa Park in Birmingham, England, July 21, 2020. /VCG)