MADRID -- Trent Alexander-Arnold was substituted just five minutes into Real Madrid's Champions League game with Marseille on Tuesday, after suffering an injury.
The right-back went to ground two minutes earlier at the Santiago Bernabéu, holding his thigh, after a spell in possession.
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Alexander-Arnold -- who joined Madrid from Liverpool in the summer -- was replaced by club captain Dani Carvajal.
Carvajal was later sent off in the 72nd minute but Madrid came from behind to win 2-1 thanks to two Kylian Mbappé goals.
The England international has started three of Madrid's five games in all competitions so far this season, with Carvajal preferred in the other two.
"It's a really good competition [between the two players]," coach Xabi Alonso said last month. "I like having that in each position, two players who want to show what they can do. It's really good for the squad."
Alexander-Arnold's England teammate Jude Bellingham returned to the Madrid squad for the Marseille game for the first time this season, after undergoing shoulder surgery in July.
However, Bellingham remained on the bench as Madrid began their Champions League campaign with a win.
