The battle for the second automatic promotion spot in League is getting closer by the week.
Barnsley have stuttered in recent weeks and their latest result - a 3-1 loss at Burton - will set alarm bells ringing among Tykes fans.
A late Cauley Woodrow goal was all the men from Oakwell had to show for their efforts as strikes by Jamie Allen, Liam Boyce and Marcus Harness earned Burton the spoils.
Barnsley are two points ahead of fourth-placed Pompey - and level with third-placed Sunderland, who needed an 88th-minute George Honeyman goal to clinch a 2-1 win at Rochdale. Earlier Charlie Wyke had cancelled out the home side's opener, scored by Ian Henderson.
Sunderland have two games in hand over Barnsley, and one over Pompey.
At the top Luton stumlbed too - with goals from James Collins and, late on, from Jason Cummings earning a 2-2 draw at home to Blackpool. The Hatters are still eight points clear at the top.
The other two sides in the play-off places both won. Charlton, in fifth, triumphed 2-0 at Plymouth thanks to goals by Lyle Taylor and Igor Vetokele, and Doncaster were 1-0 winners at basement side Bradford with a Mallik Wilks goal.
Peterborough kept up their bid to sneak into the top six with a 2-0 home win against Gillingham, while Fleetwood could only draw 2-2 with Southend, Ched Evans scoring both their goals.
AFC Wimbledon and Accrington drew 1-1 at Kingsmeadow and it was the same scoreline between Shrewsbury and Scunthorpe at the New Meadow.
Oxford won 3-1 at Walsall to do their survival hopes a lot of good, and the day's results leave Walsall, Wimbledon and Rochdale in the bottom four alongside the Bantams - but still with only six points separating 23rd from 13th.