Schalke's hopes of a morale-boosting win were dashed in a 1-0 home defeat to Kaiserslautern.
Germany goalkeeper Manuel Neuer, who on Wednesday told the Royal Blues he will not renew his contract which expires at the end of next season, was beaten in the 42nd minute by Kaiserslautern's Srdjan Lakic.
Rangnick is expected to revert largely to the side which beat holders Inter Milan 2-1 in Gelsenkirchen in the quarter-finals on 13 April when his side host United.
Spanish playmaker Jose Jurado is expected to start, as will defender Benedikt Howedes - who scored the winning goal against Inter - after sitting out yesterday's defeat with injury.
The midfield of Greece's Kyriakos Papadopoulos, Germany's Joel Matip, Alexander Baumjohann and Spain's Jurado is expected to face United after Rangnick named a totally different quartet against Kaiserslautern.
"I selected the team in such a way, because I wanted to win both of our games [against Kaiserslautern and Manchester United]," said Rangnick. "In the Champions League, we will select a different starting eleven again."
But Rangnick was disappointed with the defeat. "If you look at the entire 90 minutes, we had the better chances," said Rangnick. "But unlike Kaiserslautern, we did not use our possibilities.
"I am not dissatisfied with the defeat. The team put in a decent performance, this was the first time this particular team has played together, which has to be taken into consideration."