Hollywood siren Julia Roberts has no doubt upset one of her most famous fans, Manchester City boss Pep Guardiola, after she posed with his rivals Manchester United.

The Red Devils are on a pre-season tour of the States and Julia went along to one of their games as she’s a massive fan.

She was in the crowd to watch as Man U beat Arsenal in the friendly before running to the changing rooms for photos with manager Erik ten Hag and some of the players.

The Pretty Woman positively beamed as she was gifted a home shirt with number one on the back- thought to be a little dig at their city rivals.

JULIA ROBERTS WITH MANCHESTER UNITED PLAYERS LISANDRO MARTINEZ, JADON SANCHO AND LUKE SHAW. PIC: MANCHESTER UNITED

It’s not often premier league stars are star struck themselves, but it’s believed a number of players couldn’t believe their eyes when they saw their 55-year-old fan with many lining up for selfies with the star.

Marchus Rashford got a hug for his photo, while midfielder Casemiro and new captain couldn’t hide their delight with smiles like a Cheshire cat.

New Man U signing Mason Mount and even World Cup winner Raphael Varane got in on the act, posing with the Oscar winner.

Julia previously visited Old Trafford for a game with her husband and three kids in November 2016 when Man U was being managed by Jose Mourinho.

JULIA ROBERTS WITH MANCHESTER UNITED DEFENDER RAPHAEL VARANE. PIC: MANCHESTER UNITED

The photos will no doubt rub salt in the wounds for Manchester United’s rival boss Pep Guardiola, who previously talked about the time she visited but chose to go watch United rather than Manchester City.

He said ‘I have three idols in my life. Michael Jordan, Tiger Woods, and Julia Roberts. These are my three idols. Julia Roberts years ago came to Manchester – not in the 90s when Sir Alex (Ferguson) was winning titles and titles and titles.

JULIA ROBERTS WITH MANCHESTER UNITED CAPTAIN BRUNO FERNANDES. PIC: MANCHESTER UNITED

‘She came in the period where we were better than United, in these four or five years, right? She went to visit Manchester United, she didn’t come to see us.

‘Even if I win the Champions League it will not compare for the fact that Julia Roberts came to Manchester and not to see us.’

See more pictures of Julia with her Man United heroes in the gallery below.

Julia Roberts with Manchester United players Lisandro Martinez, Jadon Sancho and Luke Shaw. Pic: Manchester United

Julia Roberts with Manchester United star Marcus Rashford. Pic: Manchester United