Swansea boss Paul Clement does not expect to meet a weakened Manchester United side on Sunday ahead of their Europa League date with Celta Vigo.
United boss Jose Mourinho has had to balance his squad during a rigorous schedule, with the Red Devils chasing a Champions League place on two fronts.
A top-four Premier League finish remains within reach after Thursday's derby draw at Manchester City, but winning the Europa League still appears United's best option of returning to European football's top table next season.
United visit Spanish side Celta on Thursday for the first leg of their semi-final, but Clement feels that tie has no bearing on relegation-threatened Swansea's visit to Old Trafford.
"I don't think they will sacrifice our game," head coach Clement said, when asked if he felt United would rest key players this weekend.
"When you play for a club of that size and with that expectancy in front of 75,000 supporters, they are expected to give their absolute best in every game.
"They have been playing Thursday and Sunday for many weeks now and they have an injury list which I'm sure the manager is not happy with.
"But we know it will not be easy. You always hope when you play a big team at their stadium that they have a slightly off-day and you have a chance."
Eight games in 26 days have stretched Mourinho's squad to the limit, with United being hit particularly hard in central defence.
Chris Smalling, Marcos Rojo and Phil Jones have all been injured, while young defender Timothy Fosu-Mensah suffered a shoulder injury in the closing stages of Thursday's goalless draw.
Paul Pogba, Juan Mata, Zlatan Ibrahimovic are also missing through injury and Marouane Fellaini is suspended after being sent off at the Etihad Stadium.
Mourinho also has to assess the energy his players expended against City when defending for long periods.
United's 30.8 per cent possession was their lowest since those statistics were first recorded in the 2003-04 season.
"When you play a lot of games you are obviously more at risk of injuries," Clement said. "But we to perform to our best and hope the effects of all the games United have played, and their injuries, will hinder them in some way.
"It is special playing at Old Trafford and we have to go there with courage, confidence and personality to perform."
Swansea remain in the relegation zone with four games left to play and are two points adrift of 17th-placed Hull.
But they were boosted by last weekend's 2-0 home victory over Stoke and the influential return of club captain Leon Britton.
The 34-year-old had not featured since Clement's appointment at the start of January, but the diminutive midfielder set the tempo for Swansea's first win in seven games.
"You can see Leon's influence on the team, both with his technical ability and his leadership," Clement said.
"I have thought I could have used him earlier, that can always be a case with hindsight.
"But he has trained well every day and it has enabled him to have that influence and play a significant part."