"I worked all my life for that moment & I screwed everything up" - Serena Williams to Mouratoglou after USO loss to Roberta Vinci

The latest episode of "The GOAT: Serena" podcast featured Patrick Mouratoglou and Mary Carillo in conversation with former pros Chanda Rubin and Zina Garrison. The four experts discussed at length the dynamic career of Serena Williams and some of her most notable matches over the years.

Mouratoglou, Williams' coach, looked back in particular at the 2015 US Open. Williams was bidding to complete a rare Calendar Grand Slam (winning all four Majors in a single year), but she encountered a fierce challenge from unseeded Italian Roberta Vinci.

Vinci eventually prevailed in three sets to deny the American a fifth consecutive Major.

A title at Flushing Meadows would have helped Serena Williams equal the Grand Slam tally of Steffi Graf (22), the then highest Major winner of the Open Era. Williams eventually did go on to overtake Graf with 23 Slams, but Mouratoglou recalled her telling him how she had "screwed everything up" with her semifinal loss to Vinci.

"If she had won that tournament (2015 US Open) she would have won five Grand Slams in a row, including four in the same year," Patrick Mouratoglou said. "But she lost in the semis against Vinci. After she lost, she said to me 'I feel that I worked all my life for that moment and I screwed everything up', so that was a strong statement."

History has continued to beckon Serena Williams in the years since. The 40-year-old is one Slam away from equaling the all-time record of 24 Majors, which is currently held by Australia's Margaret Court.

Williams came close to accomplishing that during the 2018 and 2019 seasons - at Wimbledon and the US Open- but she ended up losing all four finals in excruciating fashion.

Patrick Mouratoglou believes Serena Williams was under the "highest possible" pressure in each of those championship matches, and claimed that she "suffered a lot" while chasing that piece of history.

"Those last few years when she was four times one match away from history is again the highest pressure I think you can have in sport," the Frenchman said. "It's the highest possible. It's a real hurdle to go through so she suffered a lot."

"It was hard to watch her feel the burden of history on her shoulders" - Mary Carillo on Serena Williams' US Open loss to Roberta Vinci

Roberta Vinci and Serena Williams at the 2015 US Open

Reputed analyst and former player Mary Carillo also weighed in on the 2015 US Open semifinal. She admitted that Serena Williams was "tight" during her match against Roberta Vinci, and more error-prone than usual.

Carillo claimed it was hard to watch her carry the "burden of history" on her shoulders.

"She won her first Major there, the highest of highs, and then she won a whole bunch more," Mary Carillo said. "When Serena lost to Vinci, she was trying to tie Steffi Graf she was trying to get to 22. Vinci had a whole attitude of not making any mistakes, and Serena made mistakes. She was tight and we could all feel it. It was hard to watch her feel the weight and burden of history on her shoulders."