United sources said Sancho was due to report for pre-season training on Friday but now say he is not due back from his holiday until next week.
Varane has still not had a medical and United are aiming to complete his £43million transfer from Real Madrid by, or on, next Wednesday.
United assembled a more senior squad for their training camp in St Andrews earlier this week but their pre-season has been hampered by the inconsistent return dates of their summer international tournament participants and a friendly with Preston that was cancelled due to a batch of lateral flow tests for Covid-19, which produced nine false positives.
“They (Sancho and Varane) still haven’t trained with us and I need to see how they are,” Solskjaer said. “I can’t see them being available for Everton but hopefully they will be ready to be on the bench [against Leeds].
“We’ve not got everyone back yet and we’re still lacking a few. Every year that there’s a championship it’s difficult. Luke [Shaw], Harry [Maguire], Fred – a few – will only have the Everton game to prepare.
“It’s still not perfect because I think teams with fewer players in tournaments do have an advantage early on but we’re as ready as we can be.
“Fred played nine games over the summer and he’s had three weeks away from us and then two weeks to get ready again, so they should be ready.”
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