When Laura Siegemund, who once reached 26th in the women’s tennis rankings, had to drop down to the I.T.F. Pro Circuit as she came back from an injury, she noticed a significant difference in the players there that went beyond skills and polish.

“There were far more small players down there, and the higher you go on the tour, the players get taller,” said Siegemund, who is 5 feet 6 inches tall. “So taller players have an advantage.”

The former United States Open champion Tracy Austin, who at 5-5 was fairly average in her day, would be undersized today.

“Martina Navratilova was thought of as tall back then, and she was 5-8,” Austin said.

She added that she was now “awe-struck” by the size and strength of the players she sees in the locker room.