Van der Sar has not played for United since the draw at Birmingham on December 28 after initially being diagnosed with 'flu.
The former Dutch international did not train yesterday or the day before and is now considered extremely doubtful for the trip to White Hart Lane this weekend.
Spell on the sidelines: Van der Sar is still reeling from flu
New United goalkeeper Anders Lindergaard was pulled out of a reserve game last night after also feeling unwell.
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