The 20-time English champions have lost their last three Premier League games following defeats by Bournemouth, Norwich City and Stoke City.
The Red Devils are winless in their last seven games in all competitions since a 2-1 victory over Watford at Vicarage Road on 21 November.
Former United striker Cole sent a message to the Red Devils fans amid mounting pressure on Louis van Gaal ahead of their game against Chelsea.
Looking forward to the game today.. Let's get behind the lads! Old Trafford fortress #mufc
— Andrew Cole (@vancole9) December 28, 2015
Van Gaal’s long-term future at Old Trafford has been called into question in recent weeks amid speculation Jose Mourinho could replace the Dutchman.
The Red Devils are in sixth place in the Premier League table and three points behind fourth-placed Tottenham Hotspur following their three-game losing run.
United are a further nine points adrift of surprise Premier League leaders Leicester City.
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