The Tigers' loss to Exeter at Sandy Park earned them a public rebuke from rugby director Richard Cockerill, who condemned the performance as unacceptable.
Life is not about to get any easier for Leicester, though, as they head to Vicarage Road tomorrow, where second-placed Saracens await them.
Leicester remain in the title play-off zone, but only just, standing one point above Exeter, while Sale Sharks, London Irish and Gloucester are also within striking distance.
McCall said: "Leicester come to us on the back of a defeat to Exeter, but before that match they had shown the type of form that has made them one of the most consistent sides in the Premiership.
"They have a squad full of internationals with a lot of experience, so we know that all aspects of our game must be at the very highest levels on Sunday."
England backs Toby Flood and Manu Tuilagi both start for Leicester, while Samoa international prop Logov Mulipola makes his full Premiership debut in a Tigers front-row shorn of Dan Cole, an injured Martin Castrogiovanni and suspended Julian White.
Scrum-half James Grindal and wing Matt Smith replace injured duo Sam Harrison and Alesana Tuilagi, respectively, while flanker Craig Newby continues his comeback from injury by being named among the replacements.
McCall makes two changes from the side that won at Wasps last time out, with scrum-half Neil de Kock and Schalk Brits starting after being used as replacements during the victory at Adams Park.
Prop Matt Stevens is named on the bench after being released by England this weekend, and scrum-half Ben Spencer returns from duty with the England Under-20 squad.
"We've enjoyed another excellent week of preparation. and we are really looking forward to this game," McCall added.
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