WIMBLEDON, England — Novak Djokovic is as pliable as Gumby, sure-footed as a mountain goat and arguably more at home on the grass of Wimbledon’s Centre Court grass than any man, with the possible exception of eight-time champion Roger Federer.

So it was unsettling to see Djokovic’s legs splay more than once Wednesday, forced to use his hands to break one fall as he sped around the court to defeat the big-serving Kevin Anderson.

It raised alarm, too, coming on the heels of Serena Williams’s tournament-ending leg injury suffered in a fall on the same stage Tuesday, just hours after Adrian Mannarino had been forced to withdraw from the event after wrenching a knee when he fell near the same spot.

Djokovic wasn’t the only experienced player to slip on Wimbledon’s lush grass Wednesday. Australia’s Nick Kyrgios, an athlete of uncommon agility, took a frightening tumble on Court No. 1 as his right leg slid out from under him, while his left knee twisted inward. After howling in pain while prone on his back, Kyrgios rose seemingly unscathed a few moments later and went on to win the five-set ordeal.

Bianca Andreescu, the 2019 U.S. Open champion, slipped roughly a half-dozen times in her second-round ouster, describing the grass on Court No. 2 as “super slippery” but not blaming it for her defeat.

As Wimbledon entered its third day, there were more questions than answers about the slickness of the grass, whether it poses a greater hazard than normal to players and what, if anything, should be done.

Tournament officials acknowledged that the persistent rains early in the week haven’t helped. Centre Court and Court No. 1, the two largest courts, have retractable roofs. But when the roofs are deployed, the moisture doesn’t evaporate as it does on courts open to the air, wind and sun.

Former pro Pam Shriver, who won five Wimbledon double championships, wondered if the venues’ air-circulation system could be improved.

Andreescu wondered if it wouldn’t help to start matches a bit later, when the grass isn’t quite so damp.

Another thought: Allowing players to wear shoes with better traction. Currently, only grass-court shoes with tiny dimples are permitted to prevent the grass from getting chewed up.

“Certainly, the conditions the first two days were as slippery as anyone has ever seen,” said Shriver, who is covering the tournament for ESPN. “Nobody wants to see what we have seen the first couple of days. Yesterday’s injuries — that was difficult to watch. They’ve got to look at everything.”

But Djokovic, a five-time Wimbledon champion, said that he didn’t believe the courts are the real problem, although he conceded the unusually high humidity seems to have made Centre Court’s grass more slippery than normal.

Instead, he said the main reason that his footing was a bit shaky Wednesday was that he hadn’t competed on grass for nearly two years, given Wimbledon’s cancellation in 2020. And the compressed, two-week turnaround between the French Open, contested on clay, and Wimbledon made the transition even tougher, said.

“[Clay] is a surface completely different in terms of movement and bounce and everything to the grass,” Djokovic said. “I think I'm still adjusting my movement, adapting myself to this surface …. Hopefully as the tournament progresses I'll also fall less, even though I don't mind falling more if the result is winning a match.”

Kyrgios downplayed cause for alarm despite his own fall, noting that a certain amount of slipping and falling is simply part of playing on grass. As an Australian who learned to play on patchy grass, he views it as an assumed risk — part of the challenge of competing on an imperfect surface.

“Look, I don’t know if there’s a solution,” Kyrgios said. “It just is what it is on the grass …. The grass has just got that unpredictable factor where it’s tough. There’s no guarantee that any time you go out there you could be injured.”

Kyrgios called it “devastating” to see Williams forced to withdraw from the tournament because of the injury, hailing her as “the G.O.A.T.”

Djokovic lamented Williams’s injury as well. But he said it didn’t enter his mind when he stepped onto Centre Court.

Second-seeded Aryna Sabalenka couldn’t say the same, however, after surviving a three-set challenge from British wild card Katie Boulter on Centre Court.

“I was thinking about that; I was hoping, ‘Hopefully I'm not going to be the player that's injured again,’” Sabalenka said, alluding to Williams’ and Mannarino’s catastrophic falls. But as her match unfolded, Sabalenka found that her footing was more sure if she kept her body lower. For whatever reason, she explained, the grass seemed softer and less slippery.

“If you stay, like, really high, then it’s getting a little bit more slippery,” she said. “You’re not moving well, you’re not stepping right. It can be slippery. It was slippery few times today. Few times I almost fall down, but it’s okay, was fine.”

Elina Svitolina brushed aside any concern, saying, “I’m sure that we wouldn’t be allowed to play on the court if the court would be in any danger for a player.”

Also Wednesday, Frances Tiafoe advanced to the third round after dispatching Vasek Pospisil, 6-4, 6-4, 6-4. Also advancing was Arlington native Denis Kudla, who trained alongside Tiafoe at College Park’s Junior Tennis Champions Center and defeated Andreas Seppi, 6-2, 6-4, 6-2.

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