The Red Devils head into the game on the back of their impressive 3-0 win over Leicester City at the King Power Stadium last weekend as they bid to break back into the Champions League qualification spots.
Jose Mourinho has been tasked with steering the Red Devils back into the top four this season after his appointment as Louis van Gaal’s successor at Old Trafford back in May.
And former Arsenal man Merson does not envisage Watford causing Manchester United any problems at Old Trafford on Saturday afternoon.
Writing in his column for Sky Sports, Merson said: “Watford have had a couple of good results but it’s hard to look past United at Old Trafford. If they sorted out their finishing they would easily be in the top four.
“When you fail to find the net a couple of times it’s unlucky, but now it has to be classed as bad finishing.”
Manchester United are currently in sixth place in the Premier League table and 14 points behind leaders Chelsea as they look to get their domestic campaign back on track under Mourinho.
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