Serena lost because of her knee. MOURATOGLOU

Serena Williams had to stop her US Open run in the semi-final against the world no.11 Karolina Pliskova.

Serena’s coach, Patrick Mouratoglou, explains why the sudden loss.

Serena couldn’t move. MOURATOGLOU

According to Patrick, the American was hindered in her movement by her left knee.

“It was quite clear,’’ Mouratoglou commented. “I don’t remember her moving so slow ever. I can’t say anything too much [about Pliskova] after [Serena] playing like this. I have to see her [Pliskova] when Serena is able to challenge her, and I’ll tell you how good she is. I don’t know.

You have to be able to move to play tennis. She couldn’t move.’’

My mind was everywhere. SERENA

Williams explained that she struggled in keeping her focus because of her injury “I wasn’t able to move the way I wanted to move,’’ Williams commented.

“When you’re injured, you’re thinking of other things when you should just be playing and thinking of your shots. My mind was just a little bit everywhere. Like I was making errors, I never make. I just blame that on thinking about my leg and just not thinking about the shot.”