The Spanish midfielder is in the dark of his future at Old Trafford and has not yet received a new agreement from club leaders.
With only eight months left to run his contract, he left the door open for the Gunners to pounce inside.
The head of Arsenal, Unai Emery, is interested in reuniting with his former colleague from Valencia.
The mail reports that Mata – which is in £ 140k per week – is waiting for an offer from the United, but it would be free to discuss terms with potential new clubs in January.
"As soon as the punishment arrived, I was sure I had to take it"
The thirty-year-old would prefer to extend his agreement with the Red Devils, but will move to remain in the Premier League and has also attracted the interest of La Liga.
Mata is one of the United players who has had a difficult relationship with United's boss Jose Mourinho in recent months.
However, major attacks in recent games against Newcastle and Juventus could see Mata back in favor in the initial formation.
Both goals were sublime free kicks that helped United go back to win both games.
Mata has revealed that she has implored the captain of United Ashley Young to take the punishment that brought his team back to level conditions against Juventus in the Champions League on Wednesday evening.
"As soon as the free kick came, I was sure I had to take it," he said.
"I said to Ash" please let me take it, because I can go over the wall. "It's very difficult for the doorman because he does not see much.
"I think that because of the place and the importance of the game, it is one of the best (I have scored)."
Mata has scored 42 goals in 198 games for the Red Devils since he arrived from Chelsea in 2014.
Since then he has won the FA Cup and the League Cup, as well as the Europa League with the club.
Mata also has 41 caps for Spain, scoring ten goals.
Unai Emery admitted the injury suffered by Danny Welbeck during the draw with Arsenal's white goal with Sporting Lisbon and had a negative effect on his players.
The stalemate in the Emirates stadiums was enough to seal the progression in the last stages of the Europa League, as they are now leading the group E.
A forgettable match was overshadowed by an injury in the first half against England striker Welbeck, who was taken to hospital after being carried on a stretcher.
"This is the worst news tonight, this injury, it is clear that we are with him in these minutes," he said.
"He was working well and he was playing a good game, he also had chances, his injury was the mentality of the players, they saw it was a big injury."