Millwall have won seven of their past 10 matches to push themselves firmly into play-off contention
Millwall held on for victory over Swansea City to give themselves hope of claiming a play-off place on the final day of the Championship season.
George Saville's close-range finish proved decisive as Swansea's run of five successive wins came to an end, with Femi Azeez hitting the woodwork for the home side before Eom Ji-Sung wasted the visitors' best chance after the break.
Millwall's fifth victory in their past six games lifts Alex Neil's side to seventh, level on points with sixth-placed Coventry City.
The Lions go to Burnley for their final regular-season game next Saturday, while Coventry – who have an advantage of four over Millwall in the goal difference column – host ninth-placed Middlesbrough, who also remain in the play-off race.
Blackburn Rovers are the other side hoping to push into the top six after victory over Watford lifted them to eighth.
Swansea's first defeat in seven matches – and just their third since caretaker boss Alan Sheehan took charge in February – means they stay 11th, with their very faint chance of reaching the play-offs now gone.
The Welsh club's fine form counted for nothing during a first half in which Millwall were too powerful for their lacklustre opponents.
Josh Coburn wasted an early chance to put Neil's men in front, shooting tamely at Lawrence Vigouroux after a rapid counter-attack.
The tone had been set, however, with Millwall's greater intent eventually rewarded when a short free-kick caused chaos in the Swansea area.
Casper De Norre and Azeez both saw shots blocked, with the latter's effort ricocheting to the far post where Saville was on hand to drive in his first goal of the season.
The half-time advantage could have been greater, with Azeez heading against the post – and then slicing the rebound wide – before his fierce half-volley was pushed to safety by Vigouroux.
Millwall's victory was their fifth in succession on their own ground, while Swansea were beaten for the first time since 15 March
After arguably their poorest half under Sheehan, Swansea improved considerably after the break.
Liam Cullen was denied a tap-in by Jake Cooper's covering challenge before the Wales forward's glorious through ball sent Eom clear, only for the South Korea forward to shoot too close to George Evans.
Millwall's third-choice goalkeeper then saved Zan Vipotnik's header and Ronald's low shot, with Vipotnik also heading wide as Swansea pushed hard for an equaliser.
But Neil's men were not to be denied, with 19-year-old Evans' first senior clean sheet securing what may yet prove a vital victory.
Millwall head coach Alex Neil:
"Yoi could see there were a lot of nerves around the game. I don't think it helps that the other game plays before us, although in this instance it worked in our favour because we knew the [Coventry] result.
"It's certainly not the best we have played. We know we can play better and we will need to play better next week if we want to try to give ourselves an opportunity.
"But what we do have is, we are always in every game, we give it everything we have got.
"I am really proud of the players for their efforts this season, but we have still got one to go."
Swansea caretaker head coach Alan Sheehan:
"There's ways to win and ways to lose. If you are going to lose, you want to lose attacking until the very end and that's what we did.
"In the first half we didn't control the madness as well as we could have done. But in the second half we made a few tactical tweaks and I thought we were really good.
"We did everything apart from score. On another day you walk away with one or three points, but we just lacked that cutting edge in the final third.
"I am happy that we went to the final whistle but obviously disappointed we didn't find the net on a number of occasions in the second half."
