The playmaking Spaniard hasn't been an often used player by Ole Gunnar Solskjaer this season but has recently found himself in the starting XI. However, tensions are high after the United States has ordered to kill Iranian General Qassem Suleimani, to avenge Iran by attacking U.S. air bases in Iraq, and to accidentally shoot down a Ukrainian passenger plane.
Solskjaer knew that there were concerns.
"There are things that worry me more than football", Solskjaer is quoted as saying by BBC Sport. "There are other things that worry me more than soccer", he said.
"He'll be tested in the next few days - we have to see for Sunday. We will stay in Europe".
Players are free to travel where they like during their break, including to Dubai, a popular destination.
Manchester United host their Premier League rivals at Old Trafford tonight looking to book their place in the fourth round, the two clubs meeting again having played out a goalless draw at Molineux earlier this month.
The manager was asked whether there was a danger United could become a team that compete only for cups, as they did primarily in the 1970s and 1980s.
"Supporters and the club alike aren't happy with not challenging for the top position in the league", said Solskjaer at Tuesday's pre-match press conference.
"That's where we feel we should be and many of today's supporters have lived that period where we won the league consistently".
"If we can get him, I think he'd definitely improve the midfield - we need a bit of experience and a bit of quality, as well - particularly against the top sides".
"We are just going to stick at it and hang in there until then, and get the performances and results and results we hope we are going to get".
After going 3 video games without a win, the Red Devils recuperated last break with a persuading 4-0 success versus Norwich City.
Solskjaer said he had no update on the situation, adding: "I've got no transfer updates, so no".