Serena Williams admitted to having "some issues" with an muscle injury after appearing to struggle in her French Open semifinal victory against Kiki Bertens.
The reigning champion looked out of sorts on Friday, particularly in the first set of her 7-6 (7), 6-4 win on Court Philippe Chatrier.
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She now faces Spain's Garbine Muguruza in Saturday's final. It's a rematch of the 2015 Wimbledon championship, which Williams won.
Muguruza, the tournament's fourth seed, had little trouble defeating Australia's Samantha Stosur, 6-2, 6-4.
Asked about possible injury issues, Williams — whose semifinal opponent was battling a calf problem — said: "Yes, I have had some issues, but it is what it is. I think it's survival of who can do the best.
"I think the first set was obviously really crucial. She's had a couple of big wins in this tournament. Being in the semifinals of a Grand Slam and having nothing to lose just really makes a big difference."
Bertens, who beat four seeds in a promising tournament for the 24-year-old, conceded Williams capitalized on her injury.
"It was really smart from Serena to hit the drop-shots," she said. "I had some problems with it.
"It was pretty tough. We were warming up this morning and we were discussing, 'OK, are we going to play or are we not going to play?' I was like, 'OK, I want to go on court. I don't want to regret it afterwards that I didn't do it.'
"So I'm really happy that I went on court. I think I played a really good match, played really aggressive tennis, so I think I can be proud of myself."