According to Athletics, Rashford was demoted from the starting lineup after arriving late for matchday training.
Flick maintains a strict policy of preventing players from starting a match if they arrive late at training sessions or team meetings.
Rashford appears to have joined Rafina, Jules Condo and Inaki Pena after undergoing the same disciplinary action.
The forward was brought to Instagram following his alternative appearance on Sunday night.
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“+3 points, Vamos Equipo (Let’s Go Team),” he wrote.
Barcelona boss Hansi Flick has addressed the choice to bench Rashford over the weekend, saying, “For Rashford, it’s normal not to play, and matches take place every three to four days. You have to keep track of his minutes.
“I saw it in Fermin. He played for minutes. We have to take that into consideration. We scored three points 3-0. Everything is great. We need to focus on the game.
“We scored three goals, but scoring three goals against a strong team isn’t always easy. We don’t want to talk about our opponents. We want to talk about our teams. We need to focus on the game and our plans.”
