The Red Devils head into the game looking to continue their push for the title and keep pace with Manchester City at the top of the Premier League table.
Manchester United are second in the table as they look to close the gap down to Manchester City before the crunch Manchester derby clash between the two sides at Old Trafford on 10 December.
The Red Devils travel to London for the second time in a matter of days, after having played Watford at Vicarage Road on Tuesday night.
And playmaker Mata has talked up the importance of Manchester United utilising their full squad of players when they take on the Gunners on Saturday.
Writing in his personal blog, One Hour Behind, Mata said: “Only four days after visiting Watford we will travel to London again, in this case to play against Arsenal.
“So, we have two consecutive away games that will require us to be very effective and competitive at all levels.
“I feel that the whole squad is absolutely involved on this and that’s a key factor because with so many fixtures we need to have the entire team focused.”
Manchester United are aiming to win the Premier League title this season after having finished in a disappointing sixth place in the top flight last season.
The Red Devils have not lifted the top flight trophy since their final triumph under Sir Alex Ferguson in the 2012-13 campaign.
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