Garnacho is known for being active on social media, while his brother also routinely posts about United matters.
This week, he liked an Instagram post in which ex-United attacker Cristiano Ronaldo criticized current manager Erik ten Hag.
United legend and Portugal captain Ronaldo gave an interview to teammate Rio Ferdinand about United and other matters.
Garnacho was caught liking a post that included some of Ronaldo’s quotes from that interview.
“Man United's coach cannot say they can’t compete to win the Premier League and the Champions League every year,” Ronaldo said.
“This is Man United! You have to be there, to mentally say… listen, maybe we don’t have that potential, but I cannot say that. We’re going to try. You have to try.
“This is why Man United need to rebuild. If Ten Hag listens to Ruud van Nistelrooy… maybe he can help. He knows the club and the club should listen to the guys who were there, as this is really important.
“Rio Ferdinand, Roy Keane, Paul Scholes, Gary Neville, Sir Alex Ferguson… you need advice from these people.
“You cannot rebuild a club without knowledge."