Foster didn’t breathe. If Keller’s stalker had a sense of drama, which apparently he did, then this was a critical moment. A dangerous moment. To the crowd, Keller was looking invincible. To Foster, she was exposed and vulnerable. His eyes scanned the crowd and he was drawn to a movement. A baseball cap, on the far side of the crowd. Climbing the stairs towards the exit. But as quickly as Foster spotted him, he was gone. Maybe it was nothing. Maybe it was something. He wasn’t sure, and without being sure he couldn’t leave Keller unwatched. Where was Tom Abbot?

Kirsten Keller went through the usual routine of bouncing the ball twice, looking once down the court and tossing the ball high into the air. It was an exact replay of the final point at Roland Garros, where she had collapsed and forfeited the game.

Not this time.

She smashed the ball hard down the court. Basilia desperately got a racket to it. It looped high into the air and hung there for what seemed like an eternity. The world slowed down and the only thing that moved was Keller, powering into the court and leaping at the ball like a striking panther. She put everything into that shot: the bitterness and humiliation of the loss in Paris, the anger at the black roses, the grief of losing Maria Rosario. The crowd burst into wild, ecstatic cheers and drowned out the umpire as he said, ‘Game, set and match, Miss Keller.’

She pumped her fists, shook hands with Marta Basilia and turned to each corner of the stadium, acknowledging the crowd with her racket held aloft. She looked to the stand and tried to pick out Foster, but he was already moving, trying to get to her. Basilia headed straight for the players’ locker room. Keller hung back, enjoying the moment. She’d undone the hoodoo of Roland Garros. Maria Rosario would have been proud.

Keller wiped her face with her wristband as she approached the fans hanging over the green hoardings, waiting for a chance for an autograph. A forest of hands reached out as she came near. They held out oversized tennis balls and programmes to sign. She grabbed at what they gave quickly and mechanically, wanting to please as many people as she could before her muscles started to tighten. A hand thrust through the crowd, close to hers. More insistent than the others. As she reached out instinctively, she felt something drop into her outstretched palm. Her blood froze as she looked down. It was a delicate silver chain. The last time she had seen it was around Maria Rosario’s neck. She looked up in horror, trying to identify Rosario’s killer in the tangle of human flesh. But the hand slipped back into the crowd like a recoiling serpent and vanished from sight.