The Swans missed out on reaching Championship play-off after they were held to a goalless draw against Doncaster.
A draw would have taken the home side back into the top-six after Blackpool failed to win their home game against Bristol City.
In a game dominated from start to finish the Swans were just unable to put the ball between the sticks.
Chance after chance came but there were no rewards for their efforts. Craig Beattie was grounded inside the box deep into injury-time, no penalty. Lee Trundle even had the ball in the net right at the death, but that was ruled out for handball.
It just wasn't Swansea City's afternoon.
David Edgar and David Cotterill have returned to the starting eleven for this crucial final day clash with Doncaster.
Left-back Edgar was a straight swap for the injured Fede Bessone to play his first game since Bristol City while Cotterill replaced Cedric van der Gun out wide.
Craig Beattie, who last featured at QPR on March 20, was also back on the bench following his injury.
Swans: Dorus de Vries; Angel Rangel, Ashley Williams, Garry Monk (C), David Edgar; Leon Britton&nbsp;(Lee Trundle, 80'), Mark Gower&nbsp;(Gorka Pintado, 58'), Darren Pratley, David Cotterill, Nathan Dyer; Shefki Kuqi&nbsp;(Craig Beattie, 70').
Not Used: David Cornell (GK), Albert Serran, Andrea Orlandi, Cedric van der Gun.
Doncaster: Ben Smith, James O'Connor, Sam Hird, Shelton Martis, Gareth Roberts (C), Mark Wilson, Jordan Mutch, James Coppinger, Dean Shiels (Mustapha Dumbuya, 89'), Jay Emmanuel-Thomas (Paul Heffernan, 76'), James Hayter.
Subs: Gary Woods (GK), Adam Lockwood, Sean McDaid, Waide Fairhurst, Robbie Clark.
Attendance: 17,630 Away: 550
Referee: G Hegley (Hertfordshire)
The atmosphere inside the Liberty was electric to get this game underway and the home side were quickest out of the blocks.
It was a game that the Swans needed to win and within two minutes they were handed an early chance from a corner, though David Cotterill's delivery was safely cleared.
Front-man Shefki Kuqi was causing problems in attack with his strength but with seven minutes played he came close to breaking the deadlock.
Angel Rangel's ball over the top of Donny's defence fell into the Finn's path but, following a series of unkindly bounces, it never sat kindly for the striker and he blazed over Ben Smith's goal.
The one-way traffic continued and minutes after the Liberty crowd erupted for hearing the latest score at Blackpool (they were losing) Kuqi was off target again after connecting with Cotterill's cross.
Pratley screwed a chance high over the top as he latched onto Rangel's pass midway through the half while Leon Britton shot wide just before the half-hour.
But the home side were handed a scare moments later when Rovers were awarded a free-kick in dangerosus territory. Arsenal loanee Jay Emmanuel-Thomas, fortunately, fired inches over the top of Dorus' goal from 20-yards but the Swans were back in familiar territory - Doncaster's penalty area - straight away where Nathan Dyer saw his weak effort cleared.
And the bombardment continued into the final 10 minutes when Pratley capitalised on a defensive slip-up to award him an opportunity which took a slight deflection, taking it inches wide for a corner, while the same player blazed over on 40 minutes following fine build-up by Mark Gower and Kuqi.
Half-Time: Swans 0 Donny
It was as you were at the start of the second period with top-scorer Pratley again coming close to breaking the deadlock, this time latching on to Dyer's through ball and beating Smith with his effort but failed to hit the target.
And David Cotterill came even closer on 51 minutes with&nbsp;a thunderous strike from distance, the 'keeper once again beaten but the ball flew into the side netting.
But Doncaster weren't just going to sit back and soak up the pressure, and with 53 on the clock Dorus was forced into making his first save of the afternoon when he got his body behind James Coppinger's strike.
The home side went 4-4-2 when when Gorka Pintado was thrown on just before the hour and his knock down from Dyer's cross almost created an opening for Kuqi whose weak effort was collected by the 'keeper.
And with time running out the tired legs of Kuqi were replaced by Craig Beattie and Scottish striker was only on the pitch a matter of minutes when he found himself through on goal, latching on to Pratley's through ball but, as he about to pill the trigger, was robbed of possession.
Lee Trundle was thrown on for the last 10 minutes to give the home side even more attacking threat, replacing Leon Britton with Ashley Williams moving up into midfield.
Another Cotterill strike from distance bounced inches wide of Smith's left-hand post but Donny substitute Paul Heffernan came agonisingly close to sneaking a winner in the very last minute but, with only de Vries to beat, he blazed high over the top.
Four minutes of added time were indicated for the Swans to find a breakthrough and a minute into that time Craig Beattie was brought down inside the area for what looked like a stonewall penalty - nothing was given.
And in the very last minute the 17,000-plus crowd packed into the Liberty Stadium thought that the Swans had done it as Lee Trundled bundled home from two-yards. No goal. Grant Hegley blows the whistle for handball before calling time on the 2009/10&nbsp;season seconds later.