Two of Serena Williams' top rivals have recently suggested the world No. 1 is guilty of questionable sportsmanship.

Li Na said Williams, who is finishing one of the best years of her career, has a unique flair for the dramatic. Sometimes Williams will start a match slow, Li said, and get stronger as the competition progresses.

“So this is the reason why she lives in Los Angeles, right?” Li joked. “No, I mean, I don’t know ‑‑ I don’t know what happened with her, but when she started the match, she’s already feeling like [she's going to] die. But in the final set, she can serve 180 [kmh, or 112 mph], 190 [kmh, or 118 mph]. I have no idea about this.”

Jelena Jankovic, a former world No. 1, went further in needling Williams with her comments:

“I never saw her [play sluggishly] when she’s leading. Every time she has a lead, she’s running for the balls and she’s hitting those big serves. For some reason, every time she starts losing, she starts serving slower or not running for certain balls. That’s something that as a player you have to pay attention to. It’s not the first time when we played that she’s doing this. That’s I think her way of playing or maybe when she plays against me. I don’t know.

“But when it’s an important moment, huge serve comes up, so you have to be on alert every time. You never know if she’s going to come slow or a really fast one. So it’s not easy to focus. It’s important for me to focus on my game and not really let those kind of things affect me and not allow me to play my game, but it’s the way it is.

“She’s the No. 1 player in the world, and she plays so well. She’s by far the best player. She deserves to be in this spot. But I think it’s also when you play, winning or losing, you have to be up there and be a good sportsman.”

This isn't the first time Williams' sportsmanship has been questioned, but these accusations aren't as strong as previous ones. Plus, Williams recently beat both Li and Jankovic, so there may be some bitterness seeping through in these remarks.

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