Real Madrid have launched an internal inquiry after winger Angel Di Maria was seen to grab his crotch following his substitution during Monday's 3-0 La Liga win against Celta Vigo.

Di Maria, who has been linked with moves to Manchester United and Arsenal, described his action as a "natural gesture" and apologised to anyone who may have found it offensive.

"I made a normal gesture as I was leaving the field," the 25-year-old told the club's official website. 

"I didn't mean it to be aimed at the fans nor the coach as people are saying. It was a normal gesture that any man would do, especially when you are running."

The incident happened after he was replaced by Real's record signing Gareth Bale.

Di Maria said he was glad the club planned to investigate the gesture, arguing it was an opportunity for him "to explain to them the situation and what happened".

"I did not spend a long time deliberately doing it, it was something natural," he added.

Real Madrid team-mate Sergio Ramos appeared to show his support for Di Maria by tweeting a photo of himself in front of a picture of singer Michael Jackson in his famous crotch-grabbing pose. 

With 18 games gone, Real, coached by Carlo Ancelotti, lie third in La Liga, five points adrift of Barcelona and Atletico Madrid.