A single shot in Jiri Lehecka’s US Open exit lit up social media, sparking accusations of cheating and forcing two Hall of Famers to step in with a rules lesson. Serena Williams’ coach Rennae Stubbs joined Martina Navratilova in defending the Czech during his third-round loss to Stefanos Tsitsipas, insisting the disputed play was entirely within the rules.

The controversy came during the second set when the game was tied 2-1, 30-30. Tsitsipas struck a forehand that landed on Lehecka’s side of the court, then spun back up and over the net on its own. The 18th seed reached his racket across to the other side and hit the ball into the net to win the point, without his racket ever touching the net itself. Online, fans complained the shot was illegal. Stubbs shut that down immediately.

“I’ve seen people ask about this play. I will explain to you,” she wrote. “This is a VERY LEGAL shot. The ball lands on Lehecka’s side then goes back over the net so you’re allowed to reach over and hit it anywhere, including into the net to win the point.”

Navratilova had already made the same point a day earlier, with considerably less patience for the criticism. “Hey loser,” she replied to a comment who called Lehecka a cheater, “this play by Lehecka was legal. All the way. Try again.”

She also responded directly to another fan questioning the shot’s legality: “Wrong :), the ball after the bounce can be hit on the other side of the net – Learn the Rules :).”

Both are right according to the rulebook. Once a ball bounces on a player’s own side and then travels to the other side, the opponent can reach across and hit it — as long as no part of the racket or body touches the net. Lehecka’s shot cleared all those criteria.

Tsitsipas went on to win the match 2-6, 6-1, 7-6(7-3), 6-1, reaching the US Open fourth round for the first time in his career after a season disrupted by back problems.

“This season might not have been the best that I’ve had, but at least I wake up every single day, I’m happy that I don’t have any pain,” Tsitsipas said afterward.

Lehecka, who reached the quarterfinals last year at the US Open, heads home from Flushing Meadows with the rules of his own winning shot needing defense from two Hall of Famers before the debate finally quieted down.