Ole Gunnar Solskjaer's decision to replace Alex Telles with Luke Shaw at half-time was purely tactical, the manager said following Manchester United's late win over Wolves.
Telles was one of six changes United made against Nuno Espirito Santo's side as Shaw dropped to the bench, but the Brazilian was withdrawn at the break after an uninspiring first-half performance from the whole team.
Shaw made an impact when he came on for Telles in the closing stages of last week's Carabao Cup win over Everton and Solskjaer repeated the change on Tuesday night but at an earlier stage in proceedings.
"It was more of a shift in the positions and a different dynamic again," Solskjaer said when asked why Telles was withdrawn. "Alex should be OK."
Solskjaer praised United's resoluteness at the back after Eric Bailly delivered an impressive performance and David de Gea made some crucial saves from close range.
"We had to defend well because they are so dangerous on the counter-attack," Solskjaer said.
"I thought Eric did fantastically well breaking up a few counters, Nemanja [Matic] second half... we adjusted a few positions in the second half to stop their counters and I think it worked, then David had to make a save and he made it.
United are next in action against Aston Villa on New Year's Day and Solskjaer believes the alterations he made against Wolves will ensure the team is fresh at the start of the new year.
"Players deserve at least two days in between games," he said. "72 hours between kick-offs I think is the minimum they should be allowed. We made six changes from the last game so that's going to stand us in good stead."