Aston Villa moved out of the Premier League relegation zone for the first time since 28 February, with one game to go, after Trezeguet's priceless winner against Arsenal.
Trezeguet beat Emiliano Martinez with a powerful first-time finish after Tyrone Mings had diverted a corner into the Egypt international's path to lift his side above managerless Watford, who had started the day 17th before a heavy 4-0 home defeat by Manchester City, on goal difference.
Villa's second win in three games sets up a dramatic final day at the bottom of the table on Sunday, which Villa will begin level on points with Watford and three points ahead of Bournemouth - with two of those three teams likely to go down.
Meanwhile, 16th-placed West Ham, who also play on Wednesday, still require one point to secure safety, although their goal difference ought to keep them up.
Arsenal, playing in their first match since reaching the FA Cup final, can now finish no higher than eighth after a disappointing performance by Mikel Arteta's side, Eddie Nketiah going closest to equalising with a header which hit the post.
However, the Gunners will still have a big say in the relegation battle when they host Watford on Sunday.
During the match, a banner reading "Back Arteta Kroenke Out' was towed by an aeroplane over Villa Park in reference to Arsenal owner Stan Kroenke.
Villa's fate back in their own hands
After Watford's 2-1 win over Newcastle on 11 July, Villa looked down and out - seven points from safety with four games to go.
But Dean Smith's side have reacted magnificently in the closing stages of the season, beating Crystal Palace, drawing at Everton before overcoming Arsenal with a gritty display oozing in character to give themselves a fighting chance of staying up.
Watford's defeat earlier on Tuesday opened the door for Villa to climb out of the relegation zone for the first time in five months heading into the final day.
Villa grasped the opportunity despite being forced to reshuffle their defence in the first half after Ahmed Elmohamady was forced off with an injury.
Smith's side have scored six goals since the restart with Trezeguet netting half of them, his latest an instinctive finish which beat Martinez for pace and power.
Villa were forced to endure some nervous moments, particularly towards the end after substitute Keinan Davis wasted a glorious chance to double the lead after firing wide.
Smith reacted to the final whistle by clenching his fist - Villa's fate back in their own hands when they meet West Ham on Sunday.
Villa will be safe if they win (presuming Watford do not win by two more goals than they do), or draw providing the Hornets do not win. But defeat would send Villa down if Watford avoid defeat or if Bournemouth win at Everton.
Gunners take a step backwards
This felt like a big step backwards for Arsenal after a positive spell in which they collected 13 points from six games.
Having followed up victory over runaway champions Liverpool by beating Manchester City to seal a first FA Cup final visit since 2017, the Gunners did not force Villa keeper Pepe Reina into a serious save.
It was the first time Villa had not faced any shots on target in a Premier League game since January 2016.
Pierre-Emerick Aubameyang's stream of goals have been a highlight of his side's season, but the Gabon forward was frustrated at Villa Park and his future remains a hot topic of conversation among supporters.
"The quicker we do it the better because the player will be more focused, more determined and more calm," said Arteta on the eve of this game when asked if Aubameyang, whose current deal expires next summer, will sign a new contract.
It was Nketiah who went closest to scoring for the visitors, the England Under-21 forward heading against the post after connecting with a corner.
The Gunners can still qualify for Europe but they will now have to win the FA Cup to play in next season's Europa League.
A 22-year wait - the stats
Villa have beaten Arsenal at Villa Park in a Premier League game for the first time since they did so in December 1998 under John Gregory, ending a run of 17 home games without a win against the Gunners.Arsenal have lost four of their six away Premier League matches since the restart.The Gunners have lost 10 league matches for a third consecutive season for the first time since a run of seven seasons between 1981-82 and 1987-88.21 of the 46 goals Arsenal have conceded in the Premier League this term have come from set-pieces.What's next?
Both teams are involved in games which affect relegation on the final day of the season - while Villa visit West Ham on Sunday (16:00 BST) looking to stay up, Arsenal round off their Premier League campaign at home to relegation-threatened Watford at the same time.
More to follow.