Wayne Rooney on the pitch during Shalka's first-leg (photo: Reuters)
Wayne Rooney and Ryan Giggs, who scored the goals in the 2-0 win in the first leg, are set to be rested at Old Trafford with Sunday's crucial Premier League match against Chelsea a few days later.
United's lead over Chelsea was cut to three points on Sunday. There are three games remaining.
Against Schalke, Ferguson is likely to hand a rare start to Michael Owen.
The winner will play either Barcelona or Real Madrid in the final at Wembley Stadium on May 28.
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