Bruce’s side face a replay with the League One outfit after a 0-0 draw at St. James’ Park just over a week ago, with a trip to West Bromwich Albion in the fifth round awaiting the winners of the clash at the Kassam Stadium.
And the Magpies boss confirmed that defensive duo Schär and Lejeune, neither of whom have started back-to-back games since the turn of the year, would be part of his line-up – which Bruce insists will be a strong one as they take on the U’s once more.
“We’ve got no alternative,” he said. “We’re still missing seven or eight, and the two lads who made their debuts, Danny (Rose) and Valentino (Lazaro), both can’t play because they weren’t registered in time, so we will be as strong as we possibly can.
“I will freshen us slightly – we’ve got two centre backs who are desperate to play in Schär and Lejeune. They’ll play, and so will the Longstaffs if they’re both fit. We’ll find out that today.
“So we will freshen things up slightly, but over the past few weeks – in the forward areas in the pitch in particular – it’s been impossible. We have to just crack on and do the best we can.”
Bruce said his side didn’t have any fresh injury concerns following Saturday’s goalless draw with Norwich City, though Emil Krafth, Javier Manquillo, Paul Dummett, Jetro Willems, Jonjo Shelvey, Dwight Gayle, Yoshinori Muto and Andy Carroll are all still sidelined.
Oxford, meanwhile, sold two of their stand-out performers in Tarique Fosu and Shandon Baptiste to Brentford last month. Both players started in the first game between the sides at St. James’ Park.
But Bruce knows United must deal with the threat posed by Robinson’s charges, who currently sit eighth in the third tier, if they’re to progress to the last 16.
“I’d seen them two or three times – when they beat West Ham comfortably, and I saw them play against Manchester City and well, and watched them on DVD two or three times,” he said.
“I understand how they’re a decent side – a good side. They’ve lost two of their players – Brentford have bought two of them, so that’ll hinder them I’m sure, but they’re a good side.
“It’s got all the classics of the FA Cup and what it is – (it’s) live on the TV and they’ll want the underdogs to turn us over. We have to be wary of that.”