Barnsley conceded a 97th-minute equaliser in a 2-2 home draw with relegated Colchester United but remain sixth in League One.
A fantastic two-goal performance from Ashley Fletcher saw Barnsley come from behind but the late leveller from Tom Lapslie means they now need a win, rather than a draw, at promoted Wigan on the final day to guarantee a place in the play-offs.
The Reds are now level on points with Scunthorpe United, who also won but have a worse goal difference, and two points clear of Gillingham who lost.
Barnsley, who kept the same team that drew at Sheffield United a week previously, almost fell behind in the first minute when George Moncur hit the post from close range after Elliott Lee beat Josh Scowen on the left of the box.
The Reds gradually found their rhythm in the first half and started to create chances, the first of which saw Sam Winnall fire over after a clever corner routine. The same player was also denied from point blank range by a brilliant save by Elliott Parish who then flung himself to his right to deny a Marc Roberts header from the resulting Conor Hourihane corner. Alfie Mawson then headed an Adam Hammill corner onto the bar when he looked certain to score.
But it was the visitors who went ahead on 43 minutes when, after what looked a clear Colchester handball near the halfway line, Lee ran to the edge of the box and slipped in Moncur to fire home.
The Reds levelled after 56 minutes when Fletcher nutmegged Tom Eastman to go clean through before firing into the bottom left corner.
Roberts was again denied a headed goal by a good Parrish save and substitute Harry Chapman fired over when well-placed ten yards out on the right of the box.
The second Barnsley goal came on 80 minutes when Chapman kept in a Hammill cross at the back post and Fletcher headed into an empty net.
Colchester goalkeeper Parrish was then stretchered off injured with striker Macauley Bonne having to go in goal as the visitors had made all three changes.
Lapslie headed in a cross from the right deep into injury-time to ruin the Oakwell party atmosphere.
