Manchester United forward Cristiano Ronaldo reportedly flew to Portugal after being told by interim boss Ralf Rangnick that he would not start in the Manchester derby on Sunday.
The 37-year-old was not involved in United's disappointing 4-1 defeat away at Manchester City, with Rangnick claiming his absence was due to a hip injury.
According to The Sun, Ronaldo was told by Rangnick that he would not start at the Etihad Stadium and wanted to use the five-time Ballon d'Or winner as an impact substitute if required.
The report adds that Ronaldo was furious at being axed from the first XI, and instead of supporting his teammates on the bench or in the stands, he opted to fly to his homeland for warm-weather training.
In addition, the report claims that the rest of United's first-team squad were left surprised by Ronaldo's decision to not join them at the team hotel or in the stadium, and believe his presence in the dressing room could have been beneficial.
Ronaldo, who is United's top goalscorer this season with 15 strikes in 30 games across all competitions, missed two fixtures against Aston Villa in January due to the same hip problem he is supposedly recovering from.