The interim Wigan boss - who recently replaced Warren Joyce until the end of the season - admits that taking on the league leaders could be a daunting prospect for his relegation-threatened side.
But the extra time to prepare has been a blessing, he believes, and he's keen to give the Latics supporters something to shout about at the weekend.
Speaking to Latics Player HD, Barrow said: "If you'd asked me a week ago how I felt about this game I'd probably have been quite on edge, but the international break has helped me and my staff more than anybody because we've managed to do a lot of work and have got into the players a bit more.
"We're confident of putting in a good performance and hopefully that brings with it the result we're looking for. "People have been telling me that we've sold out our allocation which is absolutely fantastic. The supporters clearly haven't given up so if they haven't given up then we can't give up either.
"That'll be the message to the players today and tomorrow. People are spending their earnings to support the club and it certainly helps me motivationally. If we go there and there's hardly any supporters from Wigan there it would make life harder, but I can picture them all there right at the top of the stand now backing us, and that's massive."
Newcastle were 2-0 winners at the DW Stadium earlier in the season, with Mohamed Diamé and Christian Atsu on target for Rafa Benítez's side.
But Barrow said: "I thought we gave one of our better performances when we played them back in December.
"There's things we have to do better tactically in terms of needing to be in the game and that'll be my message. If we do that then hopefully we can turn the tables on them.
"They're under as much pressure as us really but in a different way. Their supporters could become a bit anxious and that could reflect on how they play the game. We could make them quite nervous but that's got to be down to us really.
"We've always had good games against them. They've always had that attacking element about them ever since the Kevin Keegan days, and in fairness Rafael Benítez has done a good job there and they've got that attacking look about them still. They've got good footballers but it's up to us to stop them."
