Kate Middleton’s defiant appearance at the Wimbledon Tennis Championships on Sunday has given her “sustenance,” according to a report.

The Princess of Wales, 42, was greeted with a standing ovation at the annual grand slam — just four months after she revealed her cancer diagnosis to the world in March.

“This will have given her sustenance,” a palace insider told People. “She has gone through something awful and stressful, and it is crucial to have little wins to look forward to or to give you the courage and energy to go forward. And this was it.”

Kate Middleton’s defiant appearance at the Wimbledon Tennis Championships on Sunday has given her “sustenance,” according to a report.ZUMAPRESS.com

Prominent royal author Robert Jobson told the outlet that Middleton “showed a lot of courage and character, as she knew that the world was watching.”

The mom of three delighted fans as she arrived at the All England Lawn Tennis Club alongside her 9-year daughter, Princess Charlotte, and sister Pippa Middleton.

Photographer Karwai Tang, who captured the royal’s entrance, said the moment was made more special as Charlotte beamed with pride.

“She usually comes in, walks down and into her seat,” Tang told the outlet. “But she stood for a while and took it all in. For her to acknowledge it and take in the applause was special.”

The Princess of Wales, 42, was greeted with a standing ovation at the annual grand slam as she presented the players with trophies.WireImage

“Wimbledon had been waiting with bated breath for her to return, and she was back,” he added.

After the match, in which Spain’s Carlos Alcaraz defeated Novak Djokovic in straight sets, Princess Catherine presented the trophy to the defending champion and the runner-up.

The Princess was joined by her 9-year daughter, Princess Charlotte, and sister Pippa Middleton.Mirrorpix / MEGA

An expert lip reader has since decoded the beloved royal’s reaction to the roaring applause she received upon arrival at Sunday’s match-up.

Her outing came one month after she joined the royal family for King Charles’ birthday celebrations on the Buckingham Palace balcony at the Trooping the Colour ceremony.

The mom of three revealed her cancer diagnosis to the world in a pre-recorded video in March.

In a prerecorded clip shared on March 22, the Princess revealed her health woes to the world, saying doctors discovered her cancer during a planned abdominal surgery in January.

She noted that she is now in the early stages of undergoing “a course of preventative chemotherapy.”