Michael Duff is hoping for a similar atmosphere to the 4-1 win over Derby County when Barnsley host Portsmouth on Tuesday from 7.45pm.
The Reds thrashed fellow top six club Derby in their last home game and then drew 0-0 at Bristol Rovers on Saturday.
They are sixth in League One, six points clear in the play-off places, and 11 behind second-placed Plymouth with two games in hand.
Duff told the Chronicle: “Hopefully we will have a similar backing (to Derby). Games under the lights always seem to create a better atmosphere. I don’t know if it’s because people have had a couple of extra pints in the pub. The supporters have definitely come with us in the last couple of games.
“We’re not going to win every game so we need them when we’re poor and indifferent too. We’ve got too many tough games to think we are just going to score early and win every time. The fans have been great recently and so have the players. I hope they turn up with the mentality to back the team for 95 minutes no matter what happens then give their opinion at the end.”
Luca Connell could be back involved after illness at the weekend.
Duff said: “He’s feeling much better. We’ll get eyes on him today and make a decision on whether we think he’s fit enough to play.
“We missed him, he’s a good payer, but hopefully he will be back involved Tuesday night.”
Defender Robbie Cundy is back in full training after missing almost two months with a knee problem.
Pompey are tenth, nine points behind the Reds who have a game in hand.
They sacked Danny Cowley in early January following a nine-match winless run and appointed rookie manager John Mousinho who had been a player at Oxford United this season.
Mousinho has so far won six, drawn two and lost two of his nine games.
They are unbeaten in five - winning four including their last three - and have conceded just once in that run.
Duff said: “They have definitely picked up under John and you can see his methods creeping into the team. It will be a tough challenge.
“Portsmouth will still think they have a chance of the play-offs, particularly if they beat us in sixth place.
“You look at the run we have, this is definitely one of the tough ones. They are on good form.
“They have threats all over the pitch. They will be well-supported as they always are.
They probably changed manager because they felt they were under-achieving. But they are starting to put the sort of run together that their squad is capable of.”
Veteran Ryan Tunnicliffe – who played three games on loan to Barnsley from Manchester United in 2013 – has been a regular in their midfield recently.
The teams met 31 days prior to this fixture at Fratton Park, with Liam Kitching netting in the 89th minute for a 1-1 draw.
This will be the 56th meeting of the two clubs, with Barnsley winning 18 and losing 22.
The Reds are winless in the last four with three league draws and an FA Cup loss at Fratton Park in 2020.
Portsmouth’s last 14 trips to Oakwell since 1989 have seen them win once, draw three times and lose ten.
The most recent visit was a 1-1 draw in December 2018, with Cauley Woodrow equalising.